update git fetch for change

main.py

-from asyncio import subprocess
+import subprocess
 import tkinter
 import json
 import paramiko
 if __name__ == "__main__":
     check_git = subprocess.Popen(['git','merge','origin/alpha'], stdout=subprocess.PIPE, universal_newlines=True)
     stdout, stderr = check_git.communicate()
-    print(stdout)
-    if stdout != "":
+    if (stdout != "Already up to date.\n"):
         print('stdout not match')
         pass
     else: