Chore: Upgrade Go to 1.21.5 (#79329)

* bumping grafanas go version to 1.21.5

* adding how to upgrade go doc

* removing the whole ci-build and corresponding pipelines

* clarifying that we have to run make drone

* fixing starlark linter and removing unused code

* Adding note about enterprise

* trying to change the underyling image to avoid musl issues

* only need to golang one

.github/workflows/verify-kinds.yml

@@ -18,7 +18,7 @@ jobs:
       - name: "Setup Go"
         uses: "actions/setup-go@v4"
         with:
-          go-version: '1.21.3'
+          go-version: '1.21.5'
 
       - name: "Verify kinds"
         run: go run .github/workflows/scripts/kinds/verify-kinds.go