Add Maltese 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.

Description of Changes

Adds Maltese locale. :) Also fixes two white spaces in Malay locale.

[codecov[bot]]

Codecov Report

Merging #972 (5a46113) into master (06fe693) will not change coverage. The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master      #972   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           10        10           
  Lines         2036      2054   +18     
  Branches       328       330    +2     
=========================================
+ Hits          2036      2054   +18     

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

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[anishnya]

@systemcatch Assuming #970 gets merged in, this locale should be able to support dehumanize.

[jadchaar]

@anishnya does @cyriaka90 need to add the locale to any dehumanize fixtures?

[anishnya]

@jadchaar #970 hasn't been pulled in at this moment, so currently this locale wouldn't need to be added to the dehumanize fixtures.

[jadchaar]

Feel free to make any changes to other PRs @anishnya now that this is merged!