Update module github.com/prometheus/client_golang to v1.21.0#437

openshift-merge-bot[bot] merged 1 commit intomasterapp-sre/deployment-validation-operator:masterfrom

konflux/mintmaker/master/github.com-prometheus-client_golang-1.xapp-sre/deployment-validation-operator:konflux/mintmaker/master/github.com-prometheus-client_golang-1.xCopy head branch name to clipboard