Support double star globs in Dependency Scanning excluded paths

Expand support for double-star glob patterns to the DS_EXCLUDED_PATHS variable in Dependency Scanning.

This is a follow-up from #224440 (closed), and has been separated due to additional work required in the gemnasium analyser before dependencies can be upgraded to support double star globs. See this draft MR for more information.

Implementation Plan

1. Wait for Add scan.analyzer support to gemnasium to be completed. It's possible that the command package will be upgraded as part of this work (thus implicitly adding support for double star globs). If not:
2. Rebase gitlab-org/security-products/analyzers/gemnasium!353 (merged) which upgrades command to the v1.8.0 with double star glob support.