PR#1023: Expand user directory from config

Merges #1023
https://pagure.io/koji/pull-request/1023

Fixes: #1022
https://pagure.io/koji/issue/1022
home directories in config paths are not expanded

koji/__init__.py

@@ -1737,11 +1737,13 @@ def read_config(profile_name, user_config=None):
         }
     for name in cert_defaults:
         if result.get(name) is None:
-            fn = cert_defaults[name]
+            fn = os.path.expanduser(cert_defaults[name])
             if os.path.exists(fn):
                 result[name] = fn
             else:
                 result[name] = ''
+        else:
+            result[name] = os.path.expanduser(result[name])
 
     return result