Crash running jsx-no-target-blank

[dbeckwith]

With code like <a target={3} /> the jsx-no-target-blank rule crashes.

$PROJECT/node_modules/react-scripts/scripts/start.js:19
  throw err;
  ^

TypeError: attr.value.expression.value.toLowerCase is not a function
Occurred while linting $PROJECT/src/App.tsx:18
    at isTargetBlank ($PROJECT/node_modules/eslint-plugin-react/lib/rules/jsx-no-target-blank.js:26:38)
    at JSXAttribute ($PROJECT/node_modules/eslint-plugin-react/lib/rules/jsx-no-target-blank.js:94:15)
    at $PROJECT/node_modules/eslint/lib/linter/safe-emitter.js:45:58
    at Array.forEach (<anonymous>)
    at Object.emit ($PROJECT/node_modules/eslint/lib/linter/safe-emitter.js:45:38)
    at NodeEventGenerator.applySelector ($PROJECT/node_modules/eslint/lib/linter/node-event-generator.js:254:26)
    at NodeEventGenerator.applySelectors ($PROJECT/node_modules/eslint/lib/linter/node-event-generator.js:283:22)
    at NodeEventGenerator.enterNode ($PROJECT/node_modules/eslint/lib/linter/node-event-generator.js:297:14)
    at CodePathAnalyzer.enterNode ($PROJECT/node_modules/eslint/lib/linter/code-path-analysis/code-path-analyzer.js:711:23)
    at $PROJECT/node_modules/eslint/lib/linter/linter.js:952:32 {
  currentNode: <ref *1> {
    type: 'JSXAttribute',
    name: {
      type: 'JSXIdentifier',
      name: 'target',
      range: [ 406, 412 ],
      loc: {
        start: { line: 18, column: 10 },
        end: { line: 18, column: 16 }
      },
      parent: [Circular *1]
    },
    value: <ref *2> {
      type: 'JSXExpressionContainer',
      expression: {
        type: 'Literal',
        value: 3,
        raw: '3',
        range: [ 414, 415 ],
        loc: {
          start: { line: 18, column: 18 },
          end: { line: 18, column: 19 }
        },
        parent: [Circular *2]
      },
      range: [ 413, 416 ],
      loc: {
        start: { line: 18, column: 17 },
        end: { line: 18, column: 20 }
      },
      parent: [Circular *1]
    },
    range: [ 406, 416 ],
    loc: { start: { line: 18, column: 10 }, end: { line: 18, column: 20 } },
    parent: <ref *3> {
      type: 'JSXOpeningElement',
      typeParameters: undefined,
      selfClosing: false,
      name: {
        type: 'JSXIdentifier',
        name: 'a',
        range: [ 326, 327 ],
        loc: {
          start: { line: 15, column: 9 },
          end: { line: 15, column: 10 }
        },
        parent: [Circular *3]
      },
      attributes: [
        <ref *4> {
          type: 'JSXAttribute',
          name: {
            type: 'JSXIdentifier',
            name: 'className',
            range: [Array],
            loc: [Object],
            parent: [Circular *4]
          },
          value: {
            type: 'Literal',
            raw: '"App-link"',
            value: 'App-link',
            range: [Array],
            loc: [Object],
            parent: [Circular *4]
          },
          range: [ 338, 358 ],
          loc: { start: [Object], end: [Object] },
          parent: [Circular *3]
        },
        <ref *5> {
          type: 'JSXAttribute',
          name: {
            type: 'JSXIdentifier',
            name: 'href',
            range: [Array],
            loc: [Object],
            parent: [Circular *5]
          },
          value: {
            type: 'Literal',
            raw: '"https://reactjs.org"',
            value: 'https://reactjs.org',
            range: [Array],
            loc: [Object],
            parent: [Circular *5]
          },
          range: [ 369, 395 ],
          loc: { start: [Object], end: [Object] },
          parent: [Circular *3]
        },
        [Circular *1],
        <ref *6> {
          type: 'JSXAttribute',
          name: {
            type: 'JSXIdentifier',
            name: 'rel',
            range: [Array],
            loc: [Object],
            parent: [Circular *6]
          },
          value: {
            type: 'Literal',
            raw: '"noopener noreferrer"',
            value: 'noopener noreferrer',
            range: [Array],
            loc: [Object],
            parent: [Circular *6]
          },
          range: [ 427, 452 ],
          loc: { start: [Object], end: [Object] },
          parent: [Circular *3]
        }
      ],
      range: [ 325, 462 ],
      loc: { start: { line: 15, column: 8 }, end: { line: 20, column: 9 } },
      parent: <ref *8> {
        type: 'JSXElement',
        openingElement: [Circular *3],
        closingElement: <ref *7> {
          type: 'JSXClosingElement',
          name: {
            type: 'JSXIdentifier',
            name: 'a',
            range: [Array],
            loc: [Object],
            parent: [Circular *7]
          },
          range: [ 493, 497 ],
          loc: { start: [Object], end: [Object] },
          parent: [Circular *8]
        },
        children: [
          {
            type: 'JSXText',
            value: '\n          Learn React\n        ',
            raw: '\n          Learn React\n        ',
            range: [Array],
            loc: [Object],
            parent: [Circular *8]
          }
        ],
        range: [ 325, 497 ],
        loc: {
          start: { line: 15, column: 8 },
          end: { line: 22, column: 12 }
        },
        parent: <ref *9> {
          type: 'JSXElement',
          openingElement: {
            type: 'JSXOpeningElement',
            typeParameters: undefined,
            selfClosing: false,
            name: [Object],
            attributes: [Array],
            range: [Array],
            loc: [Object],
            parent: [Circular *9]
          },
          closingElement: {
            type: 'JSXClosingElement',
            name: [Object],
            range: [Array],
            loc: [Object],
            parent: [Circular *9]
          },
          children: [
            [Object],
            [Object],
            [Object],
            [Object],
            [Object],
            [Circular *8],
            [Object]
          ],
          range: [ 141, 513 ],
          loc: { start: [Object], end: [Object] },
          parent: {
            type: 'JSXElement',
            openingElement: [Object],
            closingElement: [Object],
            children: [Array],
            range: [Array],
            loc: [Object],
            parent: [Object]
          }
        }
      }
    }
  }
}