*: Add static validation to etcd_version proto annotation

tools/mod/tools.go

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//go:build tools
 // +build tools
 
 // This file implements that pattern:
@@ -33,9 +34,9 @@ import (
 	_ "github.com/mdempsky/unconvert"
 	_ "github.com/mgechev/revive"
 	_ "github.com/mikefarah/yq/v3"
+	_ "go.etcd.io/protodoc"
 	_ "gotest.tools"
 	_ "gotest.tools/gotestsum"
-	_ "go.etcd.io/protodoc"
 	_ "honnef.co/go/tools/cmd/staticcheck"
 	_ "mvdan.cc/unparam"
 )