Deprecate MigrationWorker and clean up related comments

- Removed the deprecated MigrationWorker implementation and its associated comments from the provisioning code.
- This change reflects the ongoing effort to eliminate legacy components and improve code maintainability.

pkg/registry/apis/provisioning/jobs/migrate/worker.go

@@ -14,12 +14,6 @@ type Migrator interface {
 	Migrate(ctx context.Context, rw repository.ReaderWriter, opts provisioning.MigrateJobOptions, progress jobs.JobProgressRecorder) error
 }
 
-// MigrationWorker is deprecated, as it's not safe to use today due to the lack of support for alerts and library
-// panels.
-// IMPORTANT: This worker is not registered anywhere and is not used in production.
-// We keep it around for now as a reference implementation of how a migration job could be implemented.
-// https://github.com/grafana/git-ui-sync-project/issues/604
-// https://github.com/grafana/git-ui-sync-project/issues/606
 type MigrationWorker struct {
 	unifiedMigrator Migrator
 }

pkg/registry/apis/provisioning/register.go

@@ -712,12 +712,6 @@ func (b *APIBuilder) GetPostStartHooks() (map[string]genericapiserver.PostStartH
 				10,
 			)
 
-			// MigrationWorker is deprecated, as it's not safe to use today due to the lack of support for alerts and library
-			// panels.
-			// IMPORTANT: This worker is not registered anywhere and is not used in production.
-			// We keep it around for now as a reference implementation of how a migration job could be implemented.
-			// https://github.com/grafana/git-ui-sync-project/issues/604
-			// https://github.com/grafana/git-ui-sync-project/issues/606
 			cleaner := migrate.NewNamespaceCleaner(b.clients)
 			unifiedStorageMigrator := migrate.NewUnifiedStorageMigrator(
 				cleaner,