MNT speed up plot_nca_classification.py (#21771)
MNT speed up plot_nca_classification.py (#21771)

* accelerate plot_nca_classification.py

* change step size to 0.05
manhhomienbienthuy/scikit-learn,manhhomienbienthuy/scikit-learn,betatim/scikit-learn,scikit-learn/scikit-learn,TomDLT/scikit-learn,scikit-learn/scikit-learn,jakirkham/scikit-learn,vinayak-mehta/scikit-learn,sergeyf/scikit-learn,jakirkham/scikit-learn,jakirkham/scikit-learn,scikit-learn/scikit-learn,ivannz/scikit-learn,betatim/scikit-learn,scikit-learn/scikit-learn,saiwing-yeung/scikit-learn,vinayak-mehta/scikit-learn,lesteve/scikit-learn,vinayak-mehta/scikit-learn,sergeyf/scikit-learn,AlexandreAbraham/scikit-learn,ivannz/scikit-learn,anntzer/scikit-learn,anntzer/scikit-learn,anntzer/scikit-learn,ivannz/scikit-learn,AlexandreAbraham/scikit-learn,espg/scikit-learn,manhhomienbienthuy/scikit-learn,saiwing-yeung/scikit-learn,AlexandreAbraham/scikit-learn,TomDLT/scikit-learn,lesteve/scikit-learn,manhhomienbienthuy/scikit-learn,TomDLT/scikit-learn,vinayak-mehta/scikit-learn,sergeyf/scikit-learn,TomDLT/scikit-learn,AlexandreAbraham/scikit-learn,espg/scikit-learn,espg/scikit-learn,lesteve/scikit-learn,saiwing-yeung/scikit-learn,espg/scikit-learn,betatim/scikit-learn,jakirkham/scikit-learn,anntzer/scikit-learn,ivannz/scikit-learn,lesteve/scikit-learn,sergeyf/scikit-learn,saiwing-yeung/scikit-learn,betatim/scikit-learn