Merge branch 'ivana/span-first-9-start-end' into ivana/span-first-10-random-improvements

Author: sentrivana

sentry_sdk/traces.py

@@ -471,6 +471,9 @@ def _end(self, end_timestamp: "Optional[Union[float, datetime]]" = None) -> None
         if self._scope is None:
             return
 
+        if not hasattr(self, "_previous_span_on_scope"):
+            return
+
         with capture_internal_exceptions():
             old_span = self._previous_span_on_scope
             del self._previous_span_on_scope