nilo19: fix: remove VMSS and VMSS instances from SLB backend pool only when necessary

JobBuild
105839
10-24 13:14
81eb7574
10-24 13:13
pull-kubernetes-conformance-kind-ga-only-parallel 1455053312230428672
pull-kubernetes-dependencies 1455053312062656512
pull-kubernetes-e2e-capz-conformance 1452261835490201600
pull-kubernetes-e2e-gce-100-performance 1455053312318509056
pull-kubernetes-e2e-gce-ubuntu-containerd 1455053312096210944 1452261835406315520
pull-kubernetes-e2e-kind 1455053312167514112 1452261835452452864
pull-kubernetes-e2e-kind-ipv6 1455053312201068544
pull-kubernetes-integration 1455053312133959680
pull-kubernetes-node-e2e-containerd 1455053312280760320
pull-kubernetes-typecheck 1455053312347869184
pull-kubernetes-unit 1455053312255594496
pull-kubernetes-verify 1455053313727795200
pull-kubernetes-verify-govet-levee 1455053312888934400