Force version of sklearn in examples

[damccorm]

Force sklearn version to the same version the models were trained on. This ensures that the examples will pass correctly.

Fixes #25967

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[damccorm]

Run Python 3.9 PostCommit

[codecov]

Codecov Report

Merging #25968 (27d611a) into master (3a1b641) will decrease coverage by 0.01%.
The diff coverage is 33.33%.

@@            Coverage Diff             @@
##           master   #25968      +/-   ##
==========================================
- Coverage   71.42%   71.41%   -0.01%     
==========================================
  Files         779      779              
  Lines      102530   102536       +6     
==========================================
- Hits        73228    73226       -2     
- Misses      27842    27850       +8     
  Partials     1460     1460              

Flag	Coverage Δ
python	79.95% <33.33%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...s/inference/sklearn_japanese_housing_regression.py	32.83% <33.33%> (+0.02%)	⬆️
...examples/inference/sklearn_mnist_classification.py	43.13% <33.33%> (-0.62%)	⬇️

... and 4 files with indirect coverage changes

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[tvalentyn]

will dependabot update this file?

[damccorm]

I'm not sure - I added a comment so that it will be obvious we should reject PRs that try to bump this.

[tvalentyn]

Please fix lint & yapf and run an integration test suite that runs the example.

[damccorm]

Please fix lint & yapf and run an integration test suite that runs the example.

Whoops, missed the linting failures - thanks.

Python3.9 postcommit does run the example, so that's already done. I'll run it again though.

[damccorm]

Run Python 3.9 PostCommit