Toggleable public/private upload

Rerolled #38 for 9.5.x

small compatibility fix for Drupal 10 undefined call to file_move

fix stupid issue with previous patch where i passed the plain file object to move instead of calling getFileUri on it.

The #45 patch is a small step forward but some odd things:

When creating a new Media entity with this patch enabled:

First add file, then select private storage.
-Upload a file
-Select Private storage
-Save entity
-Edit media entity again.
-Notice it has been stored as a public file.

First select storage, then upload a file.
-Set storage to private.
-Upload a file
-Notice that private has been reset to public, set to private again
-Save entity
-Edit media entity again.
-Notice is has the correct setting, private storage.

Now when you want to change the file from private to public it is not possible anymore. It will always be private.

Used correct service this time.

Try to fix patch #47.

The Needs Review Queue Bot → tested this issue.

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Please include interdiffs with all patches.

Issue summary could use some updating.