Strip off /api to get CalCat base URL

src/cal_tools/restful_config.py

@@ -54,8 +54,12 @@ def extra_calibration_client():
     if calcat_config['use-oauth2']:
         user_id, user_secret = calcat_config['user-id'], calcat_config['user-secret']
 
+    base_api_url = calcat_config['base-api-url'].rstrip('/')
+    assert base_api_url.endswith('/api')
+    base_url = base_api_url[:-4]
+
     calcat_interface2.setup_client(
-        calcat_config['base-api-url'],
+        base_url,
         client_id=user_id,
         client_secret=user_secret,
         user_email=calcat_config['user-email'],