FEAT add mask_missing_values in utils

[MatthewSZhang]

Checklist

• Used a personal fork to propose changes
• A reference to a related issue: FEAT add mask_missing_values to utils #80
• A description of the changes: add mask_missing_values function

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (84b2f83) to head (4006c59).
Report is 19 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #81   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            6         6           
  Lines          603       609    +6     
=========================================
+ Hits           603       609    +6     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.