Merge pull request #9302 from ncteisen/ruby-interop-client-quickfix

Fix ruby:{python,csharp,csharpcoreclr}_server behavior
diff --git a/src/ruby/pb/test/client.rb b/src/ruby/pb/test/client.rb
index e051676..9c4ee9c 100755
--- a/src/ruby/pb/test/client.rb
+++ b/src/ruby/pb/test/client.rb
@@ -575,7 +575,7 @@
     seen_correct_exception = false
     begin
       resp = @stub.full_duplex_call([duplex_req])
-      resp.next # triggers initial req to be sent
+      resp.each { |r| }
     rescue GRPC::Unknown => e
       if e.details != message
         fail AssertionError,