set config location to the default XDG spec

requirements.txt

@@ -1 +1,2 @@
 Mastodon.py >= 1.5.1
+pyxdg >= 0.27

tootgopher.py

@@ -4,10 +4,11 @@ import json
 import os
 import tempfile
 from subprocess import call
+from xdg import BaseDirectory
 
 # load JSON config file
 def load_config() -> dict:
-    with open('config.json') as f:
+    with open(f"{BaseDirectory.xdg_config_home}/tootgopher/config.json") as f:
         config_data = json.load(f)
     return config_data