Added base pattern / name to admin classes

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | yes
| Deprecations? | no
| Tests pass?   | ?
| Fixed tickets | N/A
| License       | MIT
| Doc PR        | N/A

This fixes the sonata admin URLs in accordance with what we do in other bundles now.