Remove noisy schema logging for unexpected member schemas

Author: Alan4506

codegen/core/src/main/java/software/amazon/smithy/python/codegen/generators/UnionGenerator.java

@@ -166,7 +166,6 @@ def _consumer(self, schema: Schema, de: ShapeDeserializer) -> None:
                         match schema.expect_member_index():
                             ${4C|}
                             case _:
-                                logger.debug("Unexpected member schema: %s", schema)
                                 self._set_result($5L(tag=schema.expect_member_name()))
 
                     def _set_result(self, value: $2T) -> None: