Support ESM for templates

[basickarl]

🚀 Feature Proposal

Support ESM templates.

Error when loading "--template": svgr-template.mjs

Error [ERR_REQUIRE_ESM]: require() of ES Module /Users/karl/development/neo4j/needle-2/packages/react/svgr-template.mjs not supported.
Instead change the require of /Users/karl/development/neo4j/needle-2/packages/react/svgr-template.mjs to a dynamic import() which is available in all CommonJS modules.
    at Option.parseArg (/Users/karl/development/neo4j/needle-2/node_modules/@svgr/cli/dist/index.js:330:22)
    at handleOptionValue (/Users/karl/development/neo4j/needle-2/node_modules/@svgr/cli/node_modules/commander/lib/command.js:539:24)
    at Command.<anonymous> (/Users/karl/development/neo4j/needle-2/node_modules/@svgr/cli/node_modules/commander/lib/command.js:566:7)
    at Command.emit (node:events:514:28)
    at Command.parseOptions (/Users/karl/development/neo4j/needle-2/node_modules/@svgr/cli/node_modules/commander/lib/command.js:1454:18)
    at Command._parseCommand (/Users/karl/development/neo4j/needle-2/node_modules/@svgr/cli/node_modules/commander/lib/command.js:1240:25)
    at Command.parse (/Users/karl/development/neo4j/needle-2/node_modules/@svgr/cli/node_modules/commander/lib/command.js:909:10)
    at Object.<anonymous> (/Users/karl/development/neo4j/needle-2/node_modules/@svgr/cli/dist/index.js:398:19)
    at Object.<anonymous> (/Users/karl/development/neo4j/needle-2/node_modules/@svgr/cli/bin/svgr:3:1)

Currently the docs do show to use CJS: https://react-svgr.com/docs/custom-templates/#custom-index-template

Motivation

The future of JS is ESM, we should be moving away from CJS everywhere.

Example

Everything re-written from CJS to ESM.

Pitch

Less pain having to deal with CJS.

Slightly related to #707

Is this on the roadmap?