Sign Drone's configuration YAML file (#36528)

* Sign Drone's configuration YAML file
This is needed to protect the repository

* Update grabpl to 2.2.8

* Add comment about generating the drone.yml file

Makefile

@@ -4,7 +4,7 @@
 
 -include local/Makefile
 
-.PHONY: all deps-go deps-js deps build-go build-server build-cli build-js build build-docker-dev build-docker-full lint-go golangci-lint test-go test-js test run run-frontend clean devenv devenv-down protobuf help
+.PHONY: all deps-go deps-js deps build-go build-server build-cli build-js build build-docker-dev build-docker-full lint-go golangci-lint test-go test-js test run run-frontend clean devenv devenv-down protobuf drone help
 
 GO = go
 GO_FILES ?= ./pkg/...
@@ -140,5 +140,13 @@ clean: ## Clean up intermediate build artifacts.
 	rm -rf node_modules
 	rm -rf public/build
 
+# This repository's configuration is protected (https://readme.drone.io/signature/).
+# Use this make target to regenerate the configuration YAML files when 
+# you modify starlark files.
+drone:
+	drone starlark
+	drone lint
+	drone --server https://drone.grafana.net sign --save grafana/grafana
+
 help: ## Display this help.
 	@awk 'BEGIN {FS = ":.*##"; printf "\nUsage:\n  make \033[36m<target>\033[0m\n"} /^[a-zA-Z_-]+:.*?##/ { printf "  \033[36m%-15s\033[0m %s\n", $$1, $$2 } /^##@/ { printf "\n\033[1m%s\033[0m\n", substr($$0, 5) } ' $(MAKEFILE_LIST)