Added variable to enable or disable archivePruner (#2458)

* Added variable to enable or disable archivePruner

* Made fixes according to code review comments

* Minor changes

pkg/storagesvc/storagesvc.go

@@ -236,7 +236,11 @@ func (ss *StorageService) Start(ctx context.Context, port int, openTracingEnable
 
 // Start runs storage service
 func Start(ctx context.Context, logger *zap.Logger, storage Storage, port int, openTracingEnabled bool) error {
-	enablePruner := true
+	enablePruner, err := strconv.ParseBool(os.Getenv("PRUNE_ENABLED"))
+	if err != nil {
+		logger.Warn("PRUNE_ENABLED value not set. Enabling archive pruner by default.", zap.Error(err))
+		enablePruner = true
+	}
 	// create a storage client
 	storageClient, err := MakeStowClient(logger, storage)
 	if err != nil {