[ENH] added version flag to openml cli

[Omswastik-11]

Fixes #1539

[jgyasu]

Nice! I am not sure if CLI is tested or not currently, but can you please add a test for this?

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 66.24%. Comparing base (3454bbb) to head (96330fc).

Files with missing lines	Patch %	Lines
openml/cli.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1555       +/-   ##
===========================================
+ Coverage   52.72%   66.24%   +13.51%     
===========================================
  Files          36       36               
  Lines        4326     4328        +2     
===========================================
+ Hits         2281     2867      +586     
+ Misses       2045     1461      -584     

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