WL#7621: Deprecate and remove mysql_find_rows.sh

The text of scripts/mysql_find_rows.sh says:

Prints all SQL queries that matches a regexp or contains a 'use database' or
'set ..' command to stdout.  A SQL query may contain newlines.  This is useful
to find things in a MySQL update log.


In other words, this script is used with the update log. But the update log was
removed in MySQL 5.0.

The script should be deprecated and removed.

See BUG#27482 mysql_find_rows: Applies to obsolete feature, should be removed