[Feature request] Add clobber option to pac modulebuilder build

[filcole]

When developing a solution sometimes an optionset/table/action/custom api can be deleted. It would be good to have a --clobber option similar to pac solution unpack to ensure that stale files generated by previous runs of pac modulebuilder build are removed.

This will allow the detection of bugs faster due to existing (plugin) code that used the classes that have been removed not compiling.

A workaround is to delete Entities/OptionSets/Messages folders in the output directory before running pac modulebuilder build

[MattB-msft]

This feature is on our backlog to add support for.