Bump gitlab-git-http-server to 0.2.8

Use SIGTERM instead of SIGKILL on aborted requests.

Replaces !443 (closed)

Would be nice to have in the next 7.14 package.

CI https://ci.gitlab.org/projects/55/refs/gitlab-git-http-server-0.2.8/commits/24e3bc8648cf8714b25f6702348208a7d35c9475

Status changed to merged

mentioned in commit 6a40008e

mentioned in commit 505de531

Cherry-picked into stable

mentioned in commit 020449ad

Thanks!