[llvm] [Github][Bazel] Add Workflow to Run Bazel Build (PR #165071)

[Jordan Rupprecht via llvm-commits]

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@@ -30,3 +30,28 @@ jobs:
       - name: Run Buildifier
         run: |
           buildifier --mode=check $(find ./utils/bazel -name *BUILD*)
+  
+  bazel-build:
+    name: "Bazel Build/Test"
+    runs-on: llvm-premerge-linux-runners
+    if: github.repository == 'llvm/llvm-project'
+    steps:
+      - name: Fetch LLVM sources
+        uses: actions/checkout at 08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        # TODO(boomanaiden154): We should use a purpose built container for this. Move
+        # over when we have fixed the issues with using custom containers with Github
+        # ARC in GKE.
+      - name: Setup System Dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y libmpfr-dev libpfm4-dev
+          sudo curl -L https://github.com/bazelbuild/bazelisk/releases/download/v1.27.0/bazelisk-amd64.deb > /tmp/bazelisk.deb
+          sudo apt-get install -y /tmp/bazelisk.deb
+          rm /tmp/bazelisk.deb
+      - name: Build/Test
+        working-directory: utils/bazel
+        run: |
+          bazel test --config=ci --sandbox_base="" \
+            @llvm-project//llvm/... \
+            @llvm-project//clang/... \
+            @llvm-project//mlir/...
----------------
rupprecht wrote:

> This patch only tests a couple projects just to get things going. The plan is to expand to more projects eventually and setup a GCS bucket for caching so jobs complete quickly by using cached artifacts.

llvm+clang+mlir is most of targets already. If you want to get this running w/ a minimal config and only add other projects once we have caching, should we start smaller? e.g. just `@llvm-project//llvm/unittests:adt_tests`

https://github.com/llvm/llvm-project/pull/165071