try not skipping on cache hit

[briantist]

Since #1119 , I've noticed that doctests run are failing, unable to find sphinx-build, unless I delete the cache and let it reinstall the dependencies. I guess the caching mechanism is not keeping the bin type files so the command sphinx-build just doesn't exist?

Trying to fix without completely uncaching...

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (27dad5b) 87.12% compared to head (c8b90df) 87.12%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1121   +/-   ##
=======================================
  Coverage   87.12%   87.12%           
=======================================
  Files          64       64           
  Lines        3162     3162           
=======================================
  Hits         2755     2755           
  Misses        407      407           

[briantist]

Seems to work! https://github.com/hvac/hvac/actions/runs/7366531054/job/20048899106?pr=1121#step:4:38

The first run did not find the cache, then I re-ran the docs job and it did find the cache. Running the install step again still had to install packages but not all of them, and it only took around 5 seconds.

The reason this is happening is because all the other runs don't install the docs group, so if another run populated the cache, then when it gets restored in this run, it does not include docs deps.

There's a possibility that in some workflow run, this job would be the first to populate a cache, and then the other jobs would all be restoring a cache that includes docs dependencies, but that is not any kind of problem.

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Merging since this has no user-facing changes.