remove now-unused rdiff file

mysql-test/main/information_schema,debug.rdiff

---- mysql-test/main/information_schema.result
-+++ mysql-test/main/information_schema.result
-@@ -2210,7 +2210,7 @@
- SELECT * FROM INFORMATION_SCHEMA.`COLUMNS` LIMIT ROWS EXAMINED 10;
- TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	COLUMN_NAME	ORDINAL_POSITION	COLUMN_DEFAULT	IS_NULLABLE	DATA_TYPE	CHARACTER_MAXIMUM_LENGTH	CHARACTER_OCTET_LENGTH	NUMERIC_PRECISION	NUMERIC_SCALE	DATETIME_PRECISION	CHARACTER_SET_NAME	COLLATION_NAME	COLUMN_TYPE	COLUMN_KEY	EXTRA	PRIVILEGES	COLUMN_COMMENT	IS_GENERATED	GENERATION_EXPRESSION
- Warnings:
--Warning	1931	Query execution was interrupted. The query examined at least 671 rows, which exceeds LIMIT ROWS EXAMINED (10). The query result may be incomplete
-+Warning	1931	Query execution was interrupted. The query examined at least 12 rows, which exceeds LIMIT ROWS EXAMINED (10). The query result may be incomplete
- #
- # End of 10.2 Test
- #