ref(hub): Delete _should_send_default_pii

We don't use this function, and since it is marked as a private method, that means we can delete it.

sentry_sdk/hub.py

@@ -59,16 +59,6 @@ def overload(x):
 _local = ContextVar("sentry_current_hub")
 
 
-def _should_send_default_pii():
-    # type: () -> bool
-    # TODO: Migrate existing code to `scope.should_send_default_pii()` and remove this function.
-    # New code should not use this function!
-    client = Hub.current.client
-    if not client:
-        return False
-    return client.should_send_default_pii()
-
-
 class _InitGuard:
     def __init__(self, client):
         # type: (Client) -> None