backend-app-api: always return true from auth.isPrincipal for unknown checks

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

packages/backend-app-api/src/services/implementations/auth/authServiceFactory.ts

@@ -147,6 +147,10 @@ class DefaultAuthService implements AuthService {
       | BackstageUserPrincipal
       | BackstageServicePrincipal;
 
+    if (type === 'unknown') {
+      return true;
+    }
+
     if (principal.type !== type) {
       return false;
     }

packages/backend-test-utils/src/next/services/MockAuthService.ts

@@ -86,6 +86,11 @@ export class MockAuthService implements AuthService {
       | BackstageUserPrincipal
       | BackstageServicePrincipal
       | BackstageNonePrincipal;
+
+    if (type === 'unknown') {
+      return true;
+    }
+
     if (principal.type !== type) {
       return false;
     }