"Clear disk space" step can be sped up

[agriyakhetarpal]

This step takes an awfully long time to complete; in many cases, it takes just about the same time or longer than it takes to build a recipe itself (if the recipe doesn't depend on many packages, that is). Maybe there is an action that can do this for us in a faster manner...

[agriyakhetarpal]

#152 speeds it up by 2x, but perhaps we could remove less space and make this even faster – I'm thinking something in the range of ~30 seconds or similar would be great (6x). I think we can reopen this to investigate more.

[ryanking13]

Probably a more fundamental change we can make is to add an option to clean up the build directory after building a recipe.