templates/summary: escape branch/tag/bookmark names in 'Download as zip' links to prevent XSS On a repository summary page, in the 'Download' section where you can download an archive of the repository at a given revision, the branch/tag names were not correctly escaped. This means that if an attacker is able to push a branch/tag/bookmark containing HTML/JavaScript in its name, then that code would be evaluated. This is a cross-site scripting (XSS) vulnerability. Fix the problem by correctly escaping the branch/tag/bookmarks. Reported by Bob Hogg <wombat@rwhogg.site> (thanks!).