Update module github.com/go-git/go-git/v5 to 5.19.1

Garret Wassermannrequested to merge
bump-go-git-dependency-1191 into main

What does this MR do?

Bump github.com/go-git/go-git/v5 to 5.19.1

Why was this MR needed?

Address CVE-2026-45022 (High severity) and other CVEs

What's the best way to test this MR?

What are the relevant issue numbers?

Merge request reports