fixed linting issues and import issues

Author: X1Vi

Diff for: requirements.txt

@@ -17,3 +17,4 @@ types-pytz
 types-requests
 gitlint>=0.13.0
 -r ./zulip/integrations/bridge_with_matrix/requirements.txt
+-r ./zulip/integrations/google/requirements.txt

Diff for: zulip/integrations/google/get-google-credentials

@@ -22,7 +22,6 @@ APPLICATION_NAME = "Zulip Calendar Bot"
 HOME_DIR = os.path.expanduser("~")
 CREDENTIALS_PATH = os.path.join(HOME_DIR, "google-credentials.json")
 
-
 def get_credentials() -> Credentials:
     """Gets valid user credentials from storage.
 
@@ -58,5 +57,7 @@ def get_credentials() -> Credentials:
 
         print("Storing credentials to " + CREDENTIALS_PATH)
 
+    return creds  # Return the obtained credentials
+
 
 get_credentials()