Update MediaController.php

| Q             | A
| ------------- | ---
| Bug fix? | no
| New feature? | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | no
| Fixed tickets |
| License       | MIT
| Doc PR        | 
Add provider and context filters for getMedia api.
- [ ] create tests
- [ ] add filters for other fields (created_at, content_typ, name etc.)
- [ ] check docs