Try improving repeated-builds performance

.github/workflows/linux-ci.yml

@@ -16,11 +16,10 @@ jobs:
       - name: Install golangci-lint
         run: curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b "$(go env GOPATH)"/bin v1.50.1
 
-      # Source: https://www.scivision.dev/github-actions-path-append/
-      #
-      # Required for the golangci-lint that we just installed to work.
+      # Required for the golangci-lint that we just installed to work. Also
+      # gives us some caching.
       - name: Add GOPATH/bin to PATH
-        run: echo "$(go env GOPATH)/bin" >> "$GITHUB_PATH"
+        uses: actions/setup-go@v3
 
       - name: Check out repository code
         uses: actions/checkout@v2

.github/workflows/windows-ci.yml

@@ -11,5 +11,9 @@ jobs:
     steps:
       - name: Check out repository code
         uses: actions/checkout@v2
+
+      # Add some caching, should help for PRs with multiple pushes.
+      - uses: actions/setup-go@v3
+
       - run: go build
       - run: go test -timeout 30s ./...