allow latest frontend_server_client (#1753)

Author: jakemac53

pkgs/test_core/CHANGELOG.md

@@ -1,6 +1,7 @@
 # 0.4.17-dev
 
 * Support the latest `package:test_api`.
+* Support the latest `package:frontend_server_client`.
 
 ## 0.4.16
 

pkgs/test_core/pubspec.yaml

@@ -13,7 +13,7 @@ dependencies:
   boolean_selector: ^2.1.0
   collection: ^1.15.0
   coverage: ^1.0.0
-  frontend_server_client: ^2.1.0
+  frontend_server_client: '>=2.1.0 <4.0.0'
   glob: ^2.0.0
   io: ^1.0.0
   meta: ^1.3.0