Add rpms-signature-scan to the konflux builds #2085

Namespace: <a href="https://detailurl.setting.custom-console-url-namespace.is.not.configured" rel="nofollow">acscs-rhacs-tenant
PipelineRun: <a href="https://console.redhat.com/application-pipeline/ns/acscs-rhacs-tenant/pipelinerun/acs-emailsender-on-pull-request-88rtp" rel="nofollow">acs-emailsender-on-pull-request-88rtp

Success

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

Status	Duration	Name
✅ Succeeded	6 seconds	init
✅ Succeeded	16 seconds	clone-repository
✅ Succeeded	3 minutes	build-container
✅ Succeeded	8 seconds	build-image-index
✅ Succeeded	11 seconds	apply-tags
✅ Succeeded	47 seconds	clair-scan
✅ Succeeded	11 seconds	rpms-signature-scan
✅ Succeeded	11 seconds	deprecated-base-image-check
✅ Succeeded	12 seconds	push-dockerfile
✅ Succeeded	52 seconds	clamav-scan
✅ Succeeded	23 seconds	ecosystem-cert-preflight-checks
✅ Succeeded	14 seconds	sast-snyk-check
✅ Succeeded	12 seconds	show-sbom
✅ Succeeded	15 seconds	show-summary