net:test_vxlan_under_vrf.sh from ubuntu_kernel_selftests failed (Check VM connectivity through VXLAN (underlay in the default VRF) [FAIL]) on Azure Standard_B1ms

[Po-Hsu Lin]

After a similar bug (bug 1871015) fixed, this test is recently found failing but only on Azure instance Standard_B1ms with K-azure

It's not a regression, failure can be found on this instance with:
 * K 5.19.0-1020 in the last cycle
 * F 5.15.0-1034 in the last cycle

Test failed with:
 Running 'make run_tests -C net TEST_PROGS=test_vxlan_under_vrf.sh TEST_GEN_PROGS='' TEST_CUSTOM_PROGS='''
 make: Entering directory '/home/azure/autotest/client/tmp/ubuntu_kernel_selftests/src/linux/tools/testing/selftests/net'
 make --no-builtin-rules ARCH=x86 -C ../../../.. headers_install
 make[1]: Entering directory '/home/azure/autotest/client/tmp/ubuntu_kernel_selftests/src/linux'
   INSTALL ./usr/include
 make[1]: Leaving directory '/home/azure/autotest/client/tmp/ubuntu_kernel_selftests/src/linux'
 TAP version 13
 1..1
 # selftests: net: test_vxlan_under_vrf.sh
 # Checking HV connectivity [ OK ]
 # Check VM connectivity through VXLAN (underlay in the default VRF) [FAIL]
 not ok 1 selftests: net: test_vxlan_under_vrf.sh # exit=1

[Po-Hsu Lin (cypressyew)]

Can be found on F-azure-5.4.0-1125, on Standard_B1ms only.