Clarify dataset_id docstring in get_dataset (fixes #1066)

[Roshangoli]

This pull request updates the docstring of the get_dataset function in openml/datasets/functions.py to clarify that the dataset_id parameter can be either:

an integer ID (e.g., 61), or

a dataset name as a string (e.g., "iris").

This improves clarity for users reading the documentation and aligns with the function's actual behavior.

Related Issue
Fixes #1066

[PGijsbers]

Hey! 👋 thanks for your contribution! Sorry for the slow reply, I was out of office and other core contributors have been busy.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.00%. Comparing base (1c60410) to head (38b29f9).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1400      +/-   ##
===========================================
- Coverage    82.94%   79.00%   -3.95%     
===========================================
  Files           38       38              
  Lines         5325     5325              
===========================================
- Hits          4417     4207     -210     
- Misses         908     1118     +210     

☔ 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.