Add query filter when searching for a table

[pkelbert]

This change adds a filter to queries SHOW TABLES on function Installer::maybe_create_table(). The queries are used intending to check if a table exists. It's faster to search only for the given name than to search among all database tables.

Fixes #2885

[nerrad]

Thanks for the pull! I can confirm this works as expected and will create the table if it doesn't exist. I also did a bit of investigation to confirm this query structure works across the MySQL versions we support.