Fixes panic when there's no user initialized (#358)

cmd/serve.go

@@ -255,10 +255,10 @@ func runServ(c *cli.Context) error {
 					"User %s does not have level %v access to repository %s",
 					user.Name, requestedMode, repoPath)
 			}
-		}
-	}
 
 			os.Setenv("GITEA_PUSHER_NAME", user.Name)
+		}
+	}
 
 	uuid := gouuid.NewV4().String()
 	os.Setenv("GITEA_UUID", uuid)