Use latest discourse module to fix caching issue

[nottrobin]

Microstack.run is using the bad version of canonicalwebteam.discourse which leads to index page caching.

Fixes https://warthogs.atlassian.net/browse/WD-4503
Fixes canonical/canonicalwebteam.discourse#165

QA

Go to https://microstack-run-233.demos.haus/docs. Change some content. Refresh.

Bear in mind that page rules set cache timeout to 1 minute anyway, so it might take 1 minute for your browser to show you the latest version.

[webteam-app]

Demo starting at https://microstack-run-233.demos.haus

[codecov]

Codecov Report

Merging #233 (7d5b65f) into main (730fb19) will not change coverage.
The diff coverage is n/a.

❗ Current head 7d5b65f differs from pull request most recent head 8160485. Consider uploading reports for the commit 8160485 to get more accurate results

@@           Coverage Diff           @@
##             main     #233   +/-   ##
=======================================
  Coverage   77.27%   77.27%           
=======================================
  Files           2        2           
  Lines          44       44           
=======================================
  Hits           34       34           
  Misses         10       10           

Flag	Coverage Δ
python	77.27% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.