DOC speed up plot_ensemble_oob.py (#21730)
DOC speed up plot_ensemble_oob.py (#21730)

* After 125, more estimators does not help the model and it improves  runtime by almost 50%

* accelerate plot_ensemble_oob.py changed max_estimator to 150 with step=5
saiwing-yeung/scikit-learn,lesteve/scikit-learn,ivannz/scikit-learn,jakirkham/scikit-learn,scikit-learn/scikit-learn,vinayak-mehta/scikit-learn,TomDLT/scikit-learn,saiwing-yeung/scikit-learn,manhhomienbienthuy/scikit-learn,lesteve/scikit-learn,jakirkham/scikit-learn,TomDLT/scikit-learn,ivannz/scikit-learn,espg/scikit-learn,sergeyf/scikit-learn,betatim/scikit-learn,saiwing-yeung/scikit-learn,TomDLT/scikit-learn,espg/scikit-learn,scikit-learn/scikit-learn,lesteve/scikit-learn,sergeyf/scikit-learn,AlexandreAbraham/scikit-learn,scikit-learn/scikit-learn,anntzer/scikit-learn,TomDLT/scikit-learn,scikit-learn/scikit-learn,anntzer/scikit-learn,ivannz/scikit-learn,espg/scikit-learn,anntzer/scikit-learn,betatim/scikit-learn,anntzer/scikit-learn,manhhomienbienthuy/scikit-learn,manhhomienbienthuy/scikit-learn,lesteve/scikit-learn,jakirkham/scikit-learn,sergeyf/scikit-learn,espg/scikit-learn,sergeyf/scikit-learn,AlexandreAbraham/scikit-learn,vinayak-mehta/scikit-learn,vinayak-mehta/scikit-learn,betatim/scikit-learn,AlexandreAbraham/scikit-learn,ivannz/scikit-learn,vinayak-mehta/scikit-learn,saiwing-yeung/scikit-learn,betatim/scikit-learn,AlexandreAbraham/scikit-learn,jakirkham/scikit-learn,manhhomienbienthuy/scikit-learn