Update pipeline-common ref to 8.18.5

Updates pipeline-common ref from 8.18.4 to 8.18.5

Changelog

8.18.5 (2024-07-09)

added (1 change)

• Add epic migration sync spec job (merge request)

Commits

https://gitlab.com/gitlab-org/quality/pipeline-common/-/compare/8.18.4...8.18.5

Merge request should be good to merge as long as pipeline for this update passes.

cc: @gl-quality/tp-sub-dept