[Hotfix][TFLite] Disable test of quantized floor mod (apache#15802)

This unit test is failing on unrelated PRs (e.g. apache#15762 at [CI link](https://ci.tlcpack.ai/blue/organizations/jenkins/tvm-arm/detail/PR-15762/4/tests)). Local testing resulted in a failed test 44 times out of 100 iterations.

tests/python/frontend/tflite/test_forward.py

@@ -2916,7 +2916,11 @@ def test_all_elemwise():
         _test_forward_elemwise(_test_floor_divide)
         _test_forward_elemwise_quantized(_test_floor_divide)
         _test_forward_elemwise(_test_floor_mod)
-        _test_forward_elemwise_quantized(_test_floor_mod)
+        # This test of quantized floor mod is currently disabled due
+        # to flaky CI failures in main, failing approximately 45% of
+        # the time.
+        #
+        # _test_forward_elemwise_quantized(_test_floor_mod)
 
 
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