test: remove useless but flaky statement

GitOrigin-RevId: 31aeec7c7f94248bee2ac1804c2c5446c3a96361

Author: zepatrik

middleware/connect_test.go

@@ -314,7 +314,6 @@ mutators:
 					_, err = clStream.CloseAndRecv()
 					assertErrDenied(t, err)
 					cClStream := connectClient.ClientStream(t.Context())
-					require.NoError(t, cClStream.Send(&rpctest.ClientStreamRequest{}))
 					_, err = cClStream.CloseAndReceive()
 					assertErrDenied(t, err)