Resolve all outstanding warnings on rendering documentation

[AA-Turner]

This PR fixes all Sphinx warnings, and enables the 'fail on warnings' mode to ensure no future regressions.

Of note:

• the markdown parser is changed to MyST, the reccomended replacement for the end-of-life recommonmark
• the footnote syntax in ARKitecture.md has been changed to Commonmark-compliant syntax
• We ignore warnings generated by Numba whilst rendering documentation
• there's a reference to the Fashion Victim model in the Journey PhD notebook, I've changed this to https://github.com/econ-ark/DemARK/blob/99948acb7b59cc9a6fb7de758972266fa4b03a06/notebooks/Fashion-Victim-Model.ipynb as the notebook was deleted.
• I opened Failure on multi-line maths with leading indentation spatialaudio/nbsphinx#753 due to this work, and introduced the \,\! construct to preserve indentation within the notebook

A

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[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (37134b9) 72.55% compared to head (8bd85bb) 72.55%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1301   +/-   ##
=======================================
  Coverage   72.55%   72.55%           
=======================================
  Files          78       78           
  Lines       13009    13009           
=======================================
  Hits         9439     9439           
  Misses       3570     3570           

Impacted Files	Coverage Δ
HARK/ConsumptionSaving/ConsIndShockModel.py	87.04% <ø> (ø)
HARK/ConsumptionSaving/ConsRiskyContribModel.py	79.81% <ø> (ø)
HARK/distribution.py	83.26% <ø> (ø)
HARK/frame.py	84.89% <ø> (ø)
HARK/interpolation.py	43.31% <ø> (ø)

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[AA-Turner]

The failure is:

worker 'gw1' crashed while running 'HARK/ConsumptionSaving/tests/test_IndShockConsumerTypeFast.py::testBufferStock::test_infinite_horizon'

@MridulS please could you confirm on this? I can't re-run failing jobs it seems, it might just be a flaky test.

A

[MridulS]

@MridulS please could you confirm on this? I can't re-run failing jobs it seems, it might just be a flaky test.

Yeah re-running this made CI happy, seems to be a flaky numba/windows test.

[MridulS]

Looks good! builds locally without any warnings :)
Thanks @AA-Turner !