analysis_options: remove unsupported error code
diff --git a/analysis_options.yaml b/analysis_options.yaml
index 5960f55..8f7fcfd 100644
--- a/analysis_options.yaml
+++ b/analysis_options.yaml
@@ -13,8 +13,6 @@
   errors:
     # treat missing required parameters as a warning (not a hint)
     missing_required_param: warning
-    # allow type narrowing
-    strong_mode_down_cast_composite: ignore
     # allow having TODOs in the code
     todo: ignore