removed function block_themes_installed() still referenced in comments

Merge request created to update the remaining comments to the new method added in https://www.drupal.org/project/drupal/issues/3533049 📌 Bulk convert the remaining hooks to OOP Active .

I had a coding standards nitpick, otherwise this looks great.

I updated the comment to resolve the coding standards issue. I didn't take the approach above as I'm not familiar enough with PHPUnit and whether the "@covers" annotation would impact code coverage reports.

Looks good to me.

I used 'git log -Sblock_themes_installed' to find where the function was changed and to confirm the new method name in the MR is correct. That agrees with what jesseh reported in #5. Also checked that there are no other instances of "block_themes_installed".

The comment is an improvement and it is wrapped correctly.

Committed to 11.x and 11.2.x

Thanks!