Add lint mixin job

.github/workflows/lint-mixins.yml

@@ -43,3 +43,41 @@ jobs:
 
       - name: List all changed mixins
         run: echo '${{ steps.changed-mixins.outputs.all_changed_files }}'
+
+  lint-mixin:
+    name: Lint Mixin
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      contents: write
+      pull-requests: write
+      repository-projects: write
+    timeout-minutes: 15
+    needs: [check-for-changed-mixins]
+    strategy:
+      matrix:
+        mixin: ${{ fromJSON(needs.check-for-changed-mixins.outputs.changed-mixins) }}
+      fail-fast: false
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: 1.18
+
+      - name: Install CI dependencies
+        run: make install-ci-deps
+
+      - name: Install Mixin dependencies
+        working-directory: ./${{ matrix.mixin }}
+        run: jb install
+
+      - name: Lint Mixin
+        working-directory: ./${{ matrix.mixin }}
+        run: mixtool lint mixin.libsonnet
+
+