Remaining deprecation errors to be D9 ready

I recently updated to the latest version of this module 8.x-2.x branch in order to prepare it for Drupal 9.
Previously, I had been using this patch
https://www.drupal.org/files/issues/2020-08-06/3148060-media_entity_vide...
from
https://www.drupal.org/project/media_entity_video/issues/3148060

Which I removed from my composer.json because those changes were committed into the version already.
But, upon running Drupal check, I am still receiving deprecation errors, that seem to have been missed:

./vendor/bin/drupal-check docroot/modules/contrib/media_entity_video
 6/6 [▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓] 100%

 ------ -------------------------------------------------------------------------------------------------------------
  Line   media_entity_video.install
 ------ -------------------------------------------------------------------------------------------------------------
  26     Call to deprecated constant FILE_EXISTS_ERROR: Deprecated in drupal:8.7.0 and is removed from drupal:9.0.0.
         Use \Drupal\Core\File\FileSystemInterface::EXISTS_ERROR.
  26     Call to deprecated function file_unmanaged_copy():
         in drupal:8.7.0 and is removed from drupal:9.0.0.
         Use \Drupal\Core\File\FileSystemInterface::copy().
 ------ -------------------------------------------------------------------------------------------------------------


 [ERROR] Found 2 errors

Looking at the committed changes from that issue
https://git.drupalcode.org/project/media_entity_video/-/commit/f3626c1de...

It's true, there is no fix for the file_unmanaged_copy() deprecation, so not sure how that was skipped since it did exist in the patches in that issue.

We need a patch to add fix this remaining issue.