Datetime display options

[silentninja]

Fixes #428

Accept display options for datetime column types.

Technical details
This PR adds a serializer to accept and validate datetime column display_options. It uses arrow library to validate format field values to accept only valid datetime object and restrict the format string based on types(date column can't accept format string with time formats).

Checklist

• My pull request has a descriptive title (not a vague title like Update index.md).
• My pull request targets the master branch of the repository
• My commit messages follow best practices.
• My code follows the established code style of the repository.
• I added tests for the changes I made (if applicable).
• I added or updated documentation (if applicable).
• I tried running the project locally and verified that there are no
  visible errors.

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[silentninja]

Blocked by #865

[codecov-commenter]

Codecov Report

Merging #885 (7babb26) into master (13289cc) will increase coverage by 0.08%.
The diff coverage is 98.36%.

@@            Coverage Diff             @@
##           master     #885      +/-   ##
==========================================
+ Coverage   93.20%   93.29%   +0.08%     
==========================================
  Files          86       86              
  Lines        3104     3160      +56     
==========================================
+ Hits         2893     2948      +55     
- Misses        211      212       +1     

Flag	Coverage Δ
pytest-backend	93.29% <98.36%> (+0.08%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
mathesar/api/display_options.py	100.00% <ø> (ø)
mathesar/reflection.py	98.70% <ø> (ø)
mathesar/api/serializers/shared_serializers.py	85.59% <98.30%> (+11.39%)	⬆️
mathesar/api/serializers/columns.py	98.76% <100.00%> (ø)

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[mathemancer]

Overall, this looks pretty good. Some comments:

• The validation is spread over two functions called in different ways, which is a bit confusing. Couldn't one call the other?
• One of the validations was missing a piece (I think; see the specific comment)
• Please make vulture happy so the pipeline passes.

[mathemancer]

Looks great to me; thanks!