Fix setting groups for published mediafiles

[Elblinator]

Current behaviour:
If a meeting adminwithout orga management permissions tries to change the groups from a publizised mediafile then the following Error is thrown:

Error: You are not allowed to perform action mediafile.update. Missing OrganizationManagementLevel: can_manage_organization

Reproduction:

1. in orga level upload file
2. publish file
3. login as a normal meeting admin
4. navigate to files and try to change the groups
5. Error is thrown

Wanted behaviour:
Anyone with the right to manage the mediafiles should be able to change the groups from the files (this includes published and meeting specific files)