fix: Correctly detect configuration for the webrtc-card live provider (#1850)

- Closes #1843

If this breaks something for you, please let me know. As a workaround,
you should manually be able to set it back to what it was with something
like:

```yaml
cameras:
 - camera_entity: camera.office
   webrtc_card:
      url: <frigate camera name>
```

tests/camera-manager/frigate/engine-frigate.test.ts

@@ -80,6 +80,7 @@ const createFrigateCameraConfig = (config?: RawFrigateCardConfig): CameraConfig
     frigate: {
       camera_name: 'camera-1',
     },
+    camera_entity: 'camera.office',
     ...config,
   });
 };
@@ -149,7 +150,7 @@ describe('getCameraEndpoints', () => {
         sign: true,
       },
       webrtcCard: {
-        endpoint: 'camera-1',
+        endpoint: 'camera.office',
       },
     });
   });