Update OLM registry builder to v4.21 to fix CVE-2025-68121 #689

Namespace: <a href="https://konflux-ui.apps.stone-prd-rh01.pg1f.p1.openshiftapps.com/ns/boilerplate-cicada-tenant" rel="nofollow">boilerplate-cicada-tenant
PipelineRun: <a href="https://konflux-ui.apps.stone-prd-rh01.pg1f.p1.openshiftapps.com/ns/boilerplate-cicada-tenant/pipelinerun/image-on-pull-request-qbh7f" rel="nofollow">image-on-pull-request-qbh7f

Success

Red Hat Konflux/image-on-pull-request has successfully validated your commit.

Status	Duration	Name
🟢 Succeeded	6 seconds	init
🟢 Succeeded	9 seconds	clone-repository
🟢 Succeeded	7 seconds	prefetch-dependencies
🟢 Succeeded	4 minutes	build-container
🟢 Succeeded	12 seconds	build-image-index
🟢 Succeeded	34 seconds	build-source-image
🟢 Succeeded	55 seconds	clair-scan
🟢 Succeeded	12 seconds	deprecated-base-image-check
🟢 Succeeded	1 minute	ecosystem-cert-preflight-checks
🟢 Succeeded	5 seconds	apply-tags
🟢 Succeeded	1 minute	clamav-scan
🟢 Succeeded	5 seconds	coverity-availability-check
🟢 Succeeded	7 seconds	push-dockerfile
🟢 Succeeded	1 minute	rpms-signature-scan
🟢 Succeeded	23 seconds	sast-shell-check
🟢 Succeeded	11 seconds	sast-snyk-check
🟢 Succeeded	8 seconds	sast-unicode-check
🟢 Succeeded	9 seconds	show-sbom