Fix usage of --print-config since it no longer supports directories

Plus we were using it weirdly before.

See:
eslint/eslint#11874

package.json

@@ -19,7 +19,7 @@
     "docs:bootstrap": "pip install -r docs/requirements.txt",
     "docs:serve": "mkdocs serve",
     "link:all": "lerna exec yarn link",
-    "lint": "eslint --no-eslintrc --c ./.eslintrc.js --cache --report-unused-disable-directives --format codeframe --ext js,jsx .",
+    "lint": "eslint --no-eslintrc --config ./.eslintrc.js --cache --report-unused-disable-directives --format codeframe --ext js,jsx .",
     "prettier:check": "prettier --ignore-path .eslintignore --check \"**/*.{css,html,js,jsx,json,md,yaml,yml}\"",
     "prettier:fix": "prettier --ignore-path .eslintignore --write \"**/*.{css,html,js,jsx,json,md,yaml,yml}\"",
     "print-version": "node -p \"require('./lerna.json').version\"",
@@ -31,11 +31,11 @@
     "release:ci": "lerna publish preminor --registry http://localhost:4873 --no-git-reset --yes",
     "test": "ava --fail-fast packages/*/test \"!packages/create-project/test\"",
     "test:create-project": "ava --verbose packages/create-project/test",
-    "validate:eslintrc:root": "eslint --no-eslintrc --print-config . -c ./.eslintrc.js > /dev/null",
-    "validate:eslintrc:eslint": "eslint --no-eslintrc --print-config . -c ./packages/eslint/eslintrc.js > /dev/null",
-    "validate:eslintrc:airbnb": "eslint --no-eslintrc --print-config . -c ./packages/airbnb/eslintrc.js > /dev/null",
-    "validate:eslintrc:airbnb-base": "eslint --no-eslintrc --print-config . -c ./packages/airbnb-base/eslintrc.js > /dev/null",
-    "validate:eslintrc:standardjs": "eslint --no-eslintrc --print-config . -c ./packages/standardjs/eslintrc.js > /dev/null",
+    "validate:eslintrc:root": "eslint --no-eslintrc --print-config ./.eslintrc.js > /dev/null",
+    "validate:eslintrc:eslint": "eslint --no-eslintrc --print-config ./packages/eslint/eslintrc.js > /dev/null",
+    "validate:eslintrc:airbnb": "eslint --no-eslintrc --print-config ./packages/airbnb/eslintrc.js > /dev/null",
+    "validate:eslintrc:airbnb-base": "eslint --no-eslintrc --print-config ./packages/airbnb-base/eslintrc.js > /dev/null",
+    "validate:eslintrc:standardjs": "eslint --no-eslintrc --print-config ./packages/standardjs/eslintrc.js > /dev/null",
     "validate:eslintrc": "yarn validate:eslintrc:eslint && yarn validate:eslintrc:airbnb-base && yarn validate:eslintrc:airbnb && yarn validate:eslintrc:standardjs && yarn validate:eslintrc:root"
   },
   "devDependencies": {