Fix "Updated:" date showing the wrong date on wiki pages

[seankross]

Problem

The "Updated:" date at the bottom of most wiki pages shows the date of the last commit to the entire repo, rather than the date the specific page was last modified.

Root Cause

The wiki uses the jekyll-last-modified-at plugin to determine each page's last-modified date. This plugin works by running git log -n 1 --format="%ct" -- <path> to find the most recent commit that touched a given file.

The Jekyll build runs inside a Docker container, and the .git directory is copied into the image via the Dockerfile's ADD command. However, GitLab CI performs a shallow clone by default (limited commit history). With a shallow clone, git sees the single available commit as having introduced every file, so git log -n 1 -- <any-file> returns the same date for all pages — the date of the most recent commit to the repo.

Fix

Added GIT_DEPTH: 0 to the build job in .gitlab-ci.yml. This tells GitLab CI to perform a deep clone, giving the jekyll-last-modified-at plugin access to the complete git history so it can correctly determine the last commit that touched each individual file.