[ci] Disable caching for setup-go

setup-go is warning because it can't find go.sum, which we don't have.

.github/workflows/bazel.yml

@@ -121,6 +121,7 @@ jobs:
       - name: Set up Go 1.15.x
         uses: actions/setup-go@v5
         with:
+          cache: false
           go-version: 1.15.x
         id: go