[KYUUBI #6446] Add tests for Spark saveToFile function

[lsm1]

:mag: Description

Issue References 🔗

This pull request fixes #6446

Describe Your Solution 🔧

Add tests for Spark saveToFile function

Types of changes :bookmark:

• [ ] Bugfix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Test Plan 🧪

Behavior Without This Pull Request :coffin:

Behavior With This Pull Request :tada:

Related Unit Tests

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Checklist 📝

• [ ] This patch was not authored or co-authored using Generative Tooling

Be nice. Be informative.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 54.73%. Comparing base (1fb1f85) to head (433f78c). Report is 29 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #6467      +/-   ##
============================================
- Coverage     58.34%   54.73%   -3.61%     
  Complexity       24       24              
============================================
  Files           656      680      +24     
  Lines         40264    43012    +2748     
  Branches       5498     5964     +466     
============================================
+ Hits          23493    23544      +51     
- Misses        14272    16957    +2685     
- Partials       2499     2511      +12     

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[lsm1]

Thanks, merged to master