Update gitlab-pages

Main changes:

* Update logrus dependency
* Update Contribution Guidelines for Wider Community
* Update module github.com/gorilla/handlers to v1.5.1
* Resolve "Gracefully handle missing Content-Length Header from API"
* Set ConfigurableRoot to default enabled

Reference: https://gitlab.com/gitlab-org/gitlab-pages/-/compare/2a21892c80bd3b229073f091206247af66344dbe...86dd2da4f0880e53cd987ab392173cd2c08aba00
Changelog: changed

GITLAB_PAGES_VERSION

-2a21892c80bd3b229073f091206247af66344dbe
+86dd2da4f0880e53cd987ab392173cd2c08aba00