Cast --inactive-conn-cleanup-timeout to float

Author: abhinavsingh

proxy/core/work/threadless.py

@@ -102,7 +102,9 @@ def __init__(
             SelectableEvents,
         ] = {}
         self.wait_timeout: float = DEFAULT_WAIT_FOR_TASKS_TIMEOUT
-        self.cleanup_inactive_timeout: float = self.flags.inactive_conn_cleanup_timeout
+        self.cleanup_inactive_timeout: float = float(
+            self.flags.inactive_conn_cleanup_timeout
+        )
         self._total: int = 0
         # When put at the top, causes circular import error
         # since integrated ssh tunnel was introduced.