Ability to add optional parameters to google_sql_user from module - Primarily : deletion_policy

[thpang]

Need the ability to pass in optional parameters to the underlying resources from this module used in database and database user creation.

Scenario: One sets up a PostgreSQL database server which then has additional infrastructure applied, a new database. Once that database is in place and one tries to delete the PostgreSQL database server it cannot given it does not have the ability to force or set the deletion_policy option of the google_sql_user resource to ABANDON. If a user owns a database and that database exists the current code just errors saying it cannot delete that user.

[morgante]

@thpang We're happy to accept a PR to add additional variables.

[github-actions[bot]]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days

[thpang]

Keeping this one open for now.