fix type hint

Author: sentrivana

sentry_sdk/_metrics.py

@@ -24,7 +24,7 @@ def _capture_metric(
 
     client = sentry_sdk.get_client()
 
-    attrs = {}  # type: dict[str, Union[str, bool, float, int]
+    attrs = {}  # type: dict[str, Union[str, bool, float, int]]
     if attributes:
         for k, v in attributes.items():
             attrs[k] = (