[L-Agbaria]

First iteration of the change, created a new S3Client class which is meant to take over the MinIOClient class.
Added a very basic test that will need to be further developed, ensured that all tests point to the same S3 client instead of MinIO.

There are still some failing tests, this is not the final version but is a partial update to allow for incremental checking and verification.

Metadata

• Reference Issue: Change MinIO to boto3 #1789
• New Tests Added: Yes
• Change Log Entry: Created S3Client and migrated MinIOClient uses to it.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 67.54386% with 37 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.10%. Comparing base (ccb5244) to head (4dca23a).

Files with missing lines	Patch %	Lines
openml/_api/clients/s3.py	63.04%	34 Missing ⚠️
openml/_api/resources/dataset.py	71.42%	2 Missing ⚠️
openml/_api/setup/backend.py	50.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1790       +/-   ##
===========================================
+ Coverage   49.48%   80.10%   +30.61%     
===========================================
  Files          63       63               
  Lines        5565     5539       -26     
===========================================
+ Hits         2754     4437     +1683     
+ Misses       2811     1102     -1709     

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