lockable_resources: longer variable name to make codacy happy

Author: cdleonard

jenkinsapi/lockable_resources.py

@@ -248,10 +248,10 @@ def wait_reserve(
                 return result
             try:
                 retry_state.check_retry()
-            except TimeoutError as e:
+            except TimeoutError as err:
                 raise ResourceReservationTimeoutError(
                     f"Timeout waiting for a resource matching {selector} after {retry}"
-                ) from e
+                ) from err
             logger.info("No free resources matching %r, retry", selector)
             self.poll()