Introduces a test for the `WP_Error` object `destination_not_deleted_move_dir` in the `move_dir()` function.
Follow up to [55226].
Props costdev, mukesh27.
Fixes#57375.
git-svn-id: https://develop.svn.wordpress.org/trunk@55244 602fd350-edb4-49c9-b593-d223f7449a82
Introduces:
- New function: `wp_opcache_invalidate_directory()`, to recursively call `wp_opcache_invalidate()` after overwriting .php files.
- New function: `move_dir()`, similar to `copy_dir()` that uses `WP_Filesystem::move()` followed by `wp_opcache_invalidate_directory()`, and has a fallback to `copy_dir()`.
Props: costdev, afragen, peterwilsoncc, sergeybiryukov, ironprogrammer, flixos90, bronsonquick, mukesh27, azaozz.
Fixes#57375.
git-svn-id: https://develop.svn.wordpress.org/trunk@55204 602fd350-edb4-49c9-b593-d223f7449a82
