fix(snuba): don't mutate filter_keys (#103177)

Some callsites are re-using the same dictionary. It causes problems when
we `del filter_keys["group_id"]` (because that mutates the input dict).

This PR runs a copy before mutating, so the original input should not be
mutated.

Author: thetruecpaul

src/sentry/utils/snuba.py

@@ -940,6 +940,7 @@ def _preprocess_group_id_redirects(self):
         in_groups = None
         out_groups: set[int | str] = set()
         if "group_id" in self.filter_keys:
+            self.filter_keys = self.filter_keys.copy()
             in_groups = get_all_merged_group_ids(self.filter_keys["group_id"])
             del self.filter_keys["group_id"]