chore: (eslint) restrict imports of @material-ui Link

BREAKING CHANGE: Added a new ESLint rule that restricts imports of Link from @material-ui

Signed-off-by: Dmitry Lobanov <lobanov.dmitry.s@gmail.com>

.changeset/great-colts-invite.md

@@ -0,0 +1,16 @@
+---
+'@backstage/cli': minor
+---
+
+Added a new ESLint rule that restricts imports of Link from @material-ui
+
+The rule can be can be overridden in the following way:
+
+```diff
+module.exports = require('@backstage/cli/config/eslint-factory')(__dirname, {
++  restrictedImports: [
++    { name: '@material-ui/core', importNames: [] },
++    { name: '@material-ui/core/Link', importNames: [] },
++  ],
+});
+```

packages/cli/config/eslint-factory.js

@@ -239,6 +239,17 @@ function createConfigForRole(dir, role, extraConfig = {}) {
             name: '@material-ui/icons/', // because this is possible too ._.
             message: "Please import '@material-ui/icons/<Icon>' instead.",
           },
+          {
+            name: '@material-ui/core',
+            importNames: ['Link'],
+            message:
+              'Prefer using `Link` from `@backstage/core-components` rather than material-UI',
+          },
+          {
+            name: '@material-ui/core/Link',
+            message:
+              'Prefer using `Link` from `@backstage/core-components` rather than material-UI',
+          },
           ...require('module').builtinModules,
           ...(extraConfig.restrictedImports ?? []),
         ],