Add support for kernel and neighbour for SHAPRFECV

[anilkumarpanda]

Problem Description
Currently SHAPRFECV does not support models such as SVM,KNN. This depends on this open issue with SHAP.Once this issue is resolved these models can be supported by SHAPRFECV.

Desired Outcome
SHAPRFECV works with SVM,KNN models.

Solution Outline

• Upgrade the SHAP version once the above issue is resolved.

• Add test to check if the explainer method is able to work with SVM,KNN models.