glob file excludes should work in buster config resources option

[GCheung55]

The resources option doesn't take a !files/to/exclude/*.js path.

The error I get is: '!files/to/exclude/*.js' matched no files.

[GCheung55]

I think it has to do with https://github.com/busterjs/buster-configuration/blob/master/lib/group.js#L146-L167.

By following the code, I determined that addResource doesn't call resolvePathsAndAddMissingResources, but appendLoad does.

resolvePathsAndAddMissingResources eventually invokes expand which does the exclusions.

[dkl-ppi]

Implemented by 6745fc6.