Appease linter

Author: iandelahorne

test/adapters/grpc/echo_service.rb

@@ -62,7 +62,7 @@ class EchoStubReturnOp < EchoStub
   # https://github.com/grpc/grpc/blob/v1.46.3/src/ruby/lib/grpc/generic/service.rb#L157-L159
   def initialize(host, creds, **kw)
     @default_metadata = { return_op: true }
-    super(host, creds, **kw)
+    super
   end
 
   # https://github.com/grpc/grpc/blob/v1.46.3/src/ruby/lib/grpc/generic/service.rb#L168-L188