Add Latin locale

[cyriaka90]

Pull Request Checklist

Thank you for taking the time to improve Arrow! Before submitting your pull request, please check all appropriate boxes:

• [x] 🧪 Added tests for changed code.
• [x] 🛠️ All tests pass when run locally (run tox or make test to find out!).
• [x] 🧹 All linting checks pass when run locally (run tox -e lint or make lint to find out!).
• [ ] 📚 Updated documentation for changed code.
• [x] ⏩ Code is up-to-date with the master branch.

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Description of Changes

Adds Latin locale. :) Unfortunately I didn't find abbreviations for the week days, therefore the full forms are listed there.

[codecov[bot]]

Codecov Report

Merging #955 (3ac0e75) into master (6941e32) will increase coverage by 0.00%. The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #955   +/-   ##
=======================================
  Coverage   99.74%   99.74%           
=======================================
  Files          10       10           
  Lines        1934     1944   +10     
  Branches      312      312           
=======================================
+ Hits         1929     1939   +10     
  Misses          4        4           
  Partials        1        1           

Impacted Files	Coverage Δ
arrow/locales.py	100.00% <100.00%> (ø)

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[cyriaka90]

Thank you! :)