Merge pull request rails#53877 from zzak/mysql-warnings-test

Fix handle_warnings with mysql2 master

Author: byroot

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -762,7 +762,6 @@ def extended_type_map_key
         def handle_warnings(sql)
           return if ActiveRecord.db_warnings_action.nil? || @raw_connection.warning_count == 0
 
-          @affected_rows_before_warnings = @raw_connection.affected_rows
           warning_count = @raw_connection.warning_count
           result = @raw_connection.query("SHOW WARNINGS")
           result = [