fix dump non-exist log directory (#9818) (#9820)

Co-authored-by: Lauris BH <lauris@nix.lv>

cmd/dump.go

@@ -145,8 +145,10 @@ func runDump(ctx *cli.Context) error {
 		}
 	}
 
-	if err := z.AddDir("log", setting.LogRootPath); err != nil {
+	if com.IsExist(setting.LogRootPath) {
-		log.Fatalf("Failed to include log: %v", err)
+		if err := z.AddDir("log", setting.LogRootPath); err != nil {
+			log.Fatalf("Failed to include log: %v", err)
+		}
 	}
 
 	if err = z.Close(); err != nil {