chore(deps): use mandrel-for-jdk21-rhel8 #124

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Status	Duration	Name
✅ Succeeded	5 seconds	init
✅ Succeeded	20 seconds	clone-repository
✅ Succeeded	3 minutes	build-container
✅ Succeeded	23 seconds	build-image-index
✅ Succeeded	15 seconds	apply-tags
✅ Succeeded	20 seconds	ecosystem-cert-preflight-checks
✅ Succeeded	39 seconds	rpms-signature-scan
✅ Succeeded	1 minute	clamav-scan
✅ Succeeded	38 seconds	sast-snyk-check
✅ Succeeded	53 seconds	push-dockerfile
✅ Succeeded	26 seconds	deprecated-base-image-check
✅ Succeeded	37 seconds	clair-scan
✅ Succeeded	33 seconds	show-summary
✅ Succeeded	21 seconds	show-sbom