RBS: reported cb_op now correctly maps input to Bravais setting

[rjgildea]

Ensure that the reported reindexing operators correctly map the input symmetry to the given Bravais settings, regardless of whether the input symmetry was a primitive or non-primitive setting

Fixes #1280 (and probably #2029)

[codecov]

Codecov Report

Merging #2105 (41fe2c6) into main (120cd59) will decrease coverage by 0.00%.
The diff coverage is 69.01%.

@@            Coverage Diff             @@
##             main    #2105      +/-   ##
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- Coverage   80.36%   80.36%   -0.01%     
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  Files         580      580              
  Lines       65698    65968     +270     
  Branches     9259     9345      +86     
==========================================
+ Hits        52800    53013     +213     
- Misses      10844    10893      +49     
- Partials     2054     2062       +8     

[graeme-winter]

Change set looks good - only concern I have is there is an ambiguity in the definition of a no-op from either None or identity -> would probably make sense to settle on either / or?

Also, I suspect there is something you have learned / already knew about, about cb ops, which would be very useful to informally share somewhere if you could think of a way of doing that? A long form comment in the top of bravais_setting code or something would seem legitimate to aid the reader once they get further down. Distinctions between hkl and abc indexing etc.

Overall though changes look good thank you