github: fix go linting

* Upgrade golangci-lint to a version built with go 1.21.x. The older
  version was a binary version built with go 1.20.x and it was failing
  against the newer code built with go 1.21.x
* print the golangci-lint version in each run to see what version of go
  it was built with in case there are incompatibilties during the next
  upgrade
* remove the linter config skipping over pkg/supervisor entirely and
  instead put in an override to ignore the `unused` linter for the
  pkg/supervisor testhelpers bits for unsed test functions necessary
  to satisfy the test interface.

.github/workflows/build.yml

@@ -311,7 +311,7 @@ jobs:
       - name: Install linters
         run: curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.52.2
       - name: Run linters
-        run: make generate && ./scripts/lint.sh -g lint
+        run: make generate && golangci-lint --version && ./scripts/lint.sh -g lint
       - name: Ensure generated proto matches
         run: |
           rm -rf node/pkg/proto

.golangci.yml

@@ -22,3 +22,9 @@ linters:
     # - unconvert # disable because extra conversion typically don't hurt but can make code more clear
     - unparam
     - prealloc
+issues:
+  exclude-rules:
+    - path: pkg/supervisor/supervisor_testhelpers.go
+      text: "^func.*supervisor.*(waitSettle|waitSettleError).*$"
+      linters:
+        - unused