Remove backend-common from permission-node

Signed-off-by: Eric Peterson <ericpeterson@spotify.com>

plugins/permission-node/src/ServerPermissionClient.ts

@@ -14,10 +14,6 @@
  * limitations under the License.
  */
 
-import {
-  TokenManager,
-  createLegacyAuthAdapters,
-} from '@backstage/backend-common';
 import {
   AuthService,
   BackstageCredentials,
@@ -53,28 +49,14 @@ export class ServerPermissionClient implements PermissionsService {
     config: Config,
     options: {
       discovery: DiscoveryService;
-      /** @deprecated This option will be removed in the future, provide a the auth option instead */
-      tokenManager?: TokenManager;
-      auth?: AuthService;
+      auth: AuthService;
     },
   ) {
-    const { discovery, tokenManager } = options;
+    const { auth, discovery } = options;
     const permissionClient = new PermissionClient({ discovery, config });
     const permissionEnabled =
       config.getOptionalBoolean('permission.enabled') ?? false;
 
-    if (
-      permissionEnabled &&
-      tokenManager &&
-      (tokenManager as any).isInsecureServerTokenManager
-    ) {
-      throw new Error(
-        'Service-to-service authentication must be configured before enabling permissions. Read more here https://backstage.io/docs/auth/service-to-service-auth',
-      );
-    }
-
-    const { auth } = createLegacyAuthAdapters(options);
-
     return new ServerPermissionClient({
       auth,
       permissionClient,