Enable copy / paste detector in megalinter

[npalm]

Remove copy paste problems and enable COPYPASTE_JSCPD

[nvuillam]

You can play with .jscpd.json to ignore some copy paste :) https://megalinter.io/latest/descriptors/copypaste_jscpd/

You can also define COPYPASTE_JSCPD_DISABLE_ERRORS_IF_LESS_THAN=N so you don't have to solve the existing copy paste issues, but prevents new ones to be published :)