tests,misc: Remove 'run' and 'build' labels

All runners are now equal, these labels are pointless.

Change-Id: I9d5fb31e20e95d30e9726d4bf0353dc87af614d7

.github/workflows/gpu-tests.yaml

@@ -11,7 +11,7 @@ on:
 
 jobs:
   build-gem5:
-    runs-on: [self-hosted, linux, x64, build]
+    runs-on: [self-hosted, linux, x64]
     container: gcr.io/gem5-test/gcn-gpu:latest
     steps:
       - uses: actions/checkout@v3
@@ -29,7 +29,7 @@ jobs:
       - run: echo "This job's status is ${{ job.status }}."
 
   HACC-tests:
-    runs-on: [self-hosted, linux, x64, build]
+    runs-on: [self-hosted, linux, x64]
     container: gcr.io/gem5-test/gcn-gpu:latest
     needs: build-gem5
     timeout-minutes: 120 # 2 hours