CU-86947ja9y dill old weights

[mart-r]

Related to #410

Tried on local (MacOS) with python3.10 - works fine
Tried on a fresh Ubuntu with python3.10 - works fine
Tried on Ubuntu with python3.11 - verified the issue

Checked the depdenency versions on Ubuntu - they were near identical (only differences being async-timeout==4.0.3 and exceptiongroup==1.2.0 additions in 3.10).

It seems to have to do with something with pickling the partial function. Perhaps the performance enhancements in 3.11 broke something?
I've verified that the config.linking.weighted_average_function value is a functools.partial and it has a keyword argument factor=0.0004 in python3.11.

So what this PR does:

• Adds a test that failed in python 3.11 (and only in 3.11) for the previous state
  • Includes a known-broken (otherwise blank) CDB in old format (which includes the config)
  • You can check out the PR on my fork for details:
    • Cu 86947ja9y dill old weights mart-r/MedCAT#27
    • The 2nd to the last commit's GHA failed due to adding the correct known-broken CDB
    • And the last on is successful due to the added fix
• Identifies and fixes the issue when setting value to config.linking.weighted_average_function
  • During loading, a default config is originally created
  • And then the data off disk is merged
  • So this means that the issue doesn't arise in the constructor / __init__
• If a method that cannot be called is found, attempts to fix it
  • Though is only able to do this if functools.partial with args and/ir kwargs to medcat.config.weighted_average is used
  • Logs that there was a change made
• If the method does not work but is not a partial of medcat.config.weighted_average the fix fails
  • This is logged as well and a workaround is suggested

This fix is only really able to remedy the default medcat.config.weighted_average method based values. Otherwise it's not straight forward to figure out what the underlying method may be.

With that said, all this PR does is apply a patch for the issue at hand. I still don't fully understand why this happens. Though I did verify that this seems to be a broader issue of saving using dill to dump functools.partial methods in older python (up to and including 3.10) and subsequently loading them in newer python (3.11+). I also verified that the issue does not seem to exist if you do the same within the same python version (be it 3.10 or 3.11).

[tomolopolis]

Task linked: CU-86947ja9y Python3.11 has issues loading old models (at least) in medcat==1.10.2

[tomolopolis]

lgtm