[AIRFLOW-XXX] Fix typos in gcp_authenticator.py (#6775)

tests/gcp/utils/gcp_authenticator.py

@@ -136,8 +136,8 @@ class GcpAuthenticator(LoggingCommandExecutor):
         """
         Sets full key path - if GCP_CONFIG_DIR points to absolute
             directory, it tries to find the key in this directory. Otherwise it assumes
-            that Airflow is run from directory where configuration i checked out
-            next to airflow directory in config directory
+            that Airflow is running from the directory where configuration is checked 
+            out next to airflow directory in config directory
             it tries to find the key folder in the workspace's config
             directory.
         :param : name of the key file to find.