Bump canonicalwebteam.discourse to 5.4.3

[jpmartinspt]

Done

Bump canonicalwebteam.discourse to 5.4.3

QA

• Check out this feature branch
• Run the site using the command ./run serve
• View the site locally in your web browser at: http://0.0.0.0:8046
• Browse the discourse powered sections in the demo environment and check they work.

[webteam-app]

Demo starting at https://charmed-kubeflow-io-170.demos.haus

[codecov]

Codecov Report

Merging #170 (0bb6ccb) into main (f587dc5) will not change coverage.
Report is 2 commits behind head on main.
The diff coverage is n/a.

❗ Current head 0bb6ccb differs from pull request most recent head 5c49aac. Consider uploading reports for the commit 5c49aac to get more accurate results

@@           Coverage Diff           @@
##             main     #170   +/-   ##
=======================================
  Coverage   77.94%   77.94%           
=======================================
  Files           3        3           
  Lines          68       68           
=======================================
  Hits           53       53           
  Misses         15       15           

Flag	Coverage Δ
python	77.94% <ø> (ø)

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