[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
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rupprecht wrote:

With regards to version pinning, this is only an issue because of mprf/pfm, right? If reproduciblity becomes an issue, we could drop those and have `--config=ci` configured to use the in-tree versions instead of the system-provided ones. It would make things slower, but more hermetic.

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