Security fixes - Wagtail 2.11.8, 2.12.5 and 2.13.2 released

[Matthew Westcott]

Hi all,
We have released Wagtail 2.11.8 (for the LTS 2.11 branch), Wagtail 2.12.5 and Wagtail 2.13.2 (for the current 2.13 branch), to fix a cross-site scripting issue with severity "medium".

For full details (including a workaround for sites unable to upgrade) please see: https://github.com/wagtail/wagtail/security/advisories/GHSA-xfrw-hxr5-ghqf

For general upgrading instructions, please see: https://docs.wagtail.io/en/stable/releases/upgrading.html

Cheers,
- Matt