[release-v1.15] Update quay.io/konflux-ci/konflux-vanguard/task-rpms-signature-scan:0.2 Docker digest to 2f3015a

[release-v1.15] Update quay.io/konflux-ci/konflux-vanguard/task-rpms-signature-scan:0.2 Docker digest to 2f3015a #1132