[TESTS][FLAKY] test_floor_divide

[tqchen]

http://ci.tvm.ai:8080/blue/rest/organizations/jenkins/pipelines/tvm/branches/PR-4375/runs/1/nodes/238/log/?start=0

[tqchen]

Could due to the extreme boundary condition at 0.5 see also #4211

[tqchen]

@kevinthesun please send a fix