sbueringer: Update cluster-api-provider-openstack OWNERS

JobBuild
22954
07-20 09:38
pull-test-infra-bazel 1421007560114180096 1417418575970308096
pull-test-infra-integration 1421007560202260480 1417418576079360000
pull-test-infra-verify-file-perms 1421007560147734528 1417418576008056832
pull-test-infra-yamllint 1421007560172900352 1417418576037416960