Refactor parse_access_* functions into BaseBuilder class

[marc-white]

Fixes #67 (or at least improves).

This PR refactors the utils functions parse_access_filename and parse_access_ncfile to be @classmethods of the builders.BaseBuilder class. The idea behind doing this is:

• The functions remain available to external callers as, e.g., BaseBuilder.parse_access_filename;
• Having them as @classmethod (as opposed to @staticmethod) gives access to the underlying class definition, so every Builder now has a list of relevant patterns (PATTERNS) that is used by default for this builder. This has the effect of causing each Builder to have its own unique list of filename regex patterns, preventing cross-contamination when new builders/patterns are added. The patterns list used can be defined by kwarg to the functions if required instead;
• Specifying a custom version of parse_access_* for a particular Builder is now easier (although I'm not sure if that's something that will ever need to be done).

Associated tests have also been updated.

[codecov]

Codecov Report

Attention: Patch coverage is 98.50746% with 1 line in your changes missing coverage. Please review.

Project coverage is 96.96%. Comparing base (a808275) to head (8465fb7).

Files	Patch %	Lines
src/access_nri_intake/source/builders.py	98.50%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #181   +/-   ##
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  Coverage   96.96%   96.96%           
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  Files           9        9           
  Lines         626      626           
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  Hits          607      607           
  Misses         19       19           

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[dougiesquire]

Thanks for this @marc-white!

I guess the main difference in having these as @classmethods, rather than just having source.utils.parse_access_ncfile receive an additional input for the patterns (which are an attribute on each Builder class) is that it allows overriding the parse_access_ncfile and/or parse_access_filename. I'm not sure whether that will ever be needed, but I guess there's no reason not to add that additional flexibility.

[marc-white]

@dougiesquire is there any other process we need to tick off before I merge this back in, or is the accepted review enough?

[dougiesquire]

An accepted review and the passing checks is sufficient. Please feel free to merge