Support for other file types (erb)

### Product

axe-core

### Feature Description

I was looking into using the axe Accessibility Linter in VSCode for a Rails project, and was trying to find if there was an option to add additional file types to detection. In this particular case they would be `x.html.erb` files.

Is there a way to do this? If not could a configuration option be added to enable this? I appreciate that it will not be 100% supported on some of the ERB templating syntax, but it would still be potentially very useful even ignoring ERB.