Update dependency homebrew/openshift-cli to v4.21.7

Author: renovate[bot]

confbatstest/Dockerfile_build

@@ -26,7 +26,7 @@ ARG HELM_VERSION=v4.0.4
 # renovate: datasource=github-releases depName=stedolan/jq
 ARG JQ_VERSION=1.6
 # renovate: datasource=repology depName=homebrew/openshift-cli
-ARG OC_VERSION=4.20.6
+ARG OC_VERSION=4.21.7
 # renovate: datasource=github-releases depName=open-policy-agent/opa
 ARG OPA_VERSION=v1.11.0
 # renovate: datasource=github-releases depName=open-policy-agent/conftest