Migrate to ESLint 9

.github/workflows/build-lint-test.yml

@@ -168,10 +168,6 @@ jobs:
     name: Lint
     runs-on: ubuntu-latest
     needs: prepare
-    strategy:
-      fail-fast: false
-      matrix:
-        package-name: ${{ fromJson(needs.prepare.outputs.all-workspace-package-names) }}
     steps:
       - uses: actions/checkout@v4
       - name: Setup Node
@@ -180,7 +176,8 @@ jobs:
           node-version-file: '.nvmrc'
           cache: yarn
       - run: yarn --immutable --immutable-cache
-      - run: yarn workspace ${{ matrix.package-name }} run lint:ci
+      - name: Lint
+        run: yarn lint
       - name: Require clean working directory
         shell: bash
         run: |

.prettierrc.js → .prettierrc.mjs

@@ -1,8 +1,11 @@
 // All of these are defaults except singleQuote, but we specify them
 // for explicitness
-module.exports = {
+const config = {
   quoteProps: 'as-needed',
   singleQuote: true,
   tabWidth: 2,
   trailingComma: 'all',
+  plugins: ['prettier-plugin-packagejson'],
 };
+
+export default config;