Add a few more types for edge cases

[mesozoic]

This adds a few more elements to pyairtable.api.types:

• CollaboratorEmailDict, which represents {"email": "foo@bar.com"}
  • This is not a value that the API will return, but it is a valid value to write to the API.
• FormulaErrorDict to represent {"error": "#ERROR!"}
• FormulaNotANumberDict to represent {"specialValue": "NaN"}
• is_airtable_error(obj) to check for the two values above

[codecov[bot]]

Codecov Report

Merging #270 (a7d8ca5) into main (a0bf59b) will increase coverage by 0.08%. The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #270      +/-   ##
==========================================
+ Coverage   93.22%   93.30%   +0.08%     
==========================================
  Files          16       16              
  Lines         826      836      +10     
==========================================
+ Hits          770      780      +10     
  Misses         56       56              

Impacted Files	Coverage Δ
pyairtable/api/types.py	100.00% <100.00%> (ø)