Disable `iree_tfl_tests/vmvx_mobilebert_tf2_quant.run`. (#15822)

Too slow for CI and the matching llvmcpu test is also disabled for a
(possibly stale) correctness issue.

ci-exactly: build_all,test_tf_integrations,test_tf_integrations_gpu
diff --git a/integrations/tensorflow/test/iree_tfl_tests/vmvx_mobilebert_tf2_quant.run b/integrations/tensorflow/test/iree_tfl_tests/vmvx_mobilebert_tf2_quant.run
index 63c8663..210fe0a 100644
--- a/integrations/tensorflow/test/iree_tfl_tests/vmvx_mobilebert_tf2_quant.run
+++ b/integrations/tensorflow/test/iree_tfl_tests/vmvx_mobilebert_tf2_quant.run
@@ -1,2 +1,5 @@
 # REQUIRES: vmvx
+# REQUIRES: bugfix
+#           Numeric error on llvmcpu (#9796)
+#           Too slow for CI (9 minutes)
 # RUN: %PYTHON -m iree_tfl_tests.mobilebert_tf2_quant_test --target_backend=vmvx --artifacts_dir=%t