feature: customize/replace checkout command

[ashanbrown]

I'd like to be able to customize/replace the checkout command in order to do a shallow clone. circleci checkout takes some options for this, so we could pass through options from a parameter, or we could just allow replacing the entire checkout command.

[jennifer-shehane]

@ashanbrown I apologize for such a late reply on this request. If you haven't already found a solution, could you provide an example of what you want to do with checkout? I don't see how this shouldn't be possible with our orb. Maybe try out our v 3.0.0 orb also since we changed nearly everything in how it executes.

[emilyrohrbough]

@jennifer-shehane The cypress/install job would need a new parameter to skip the checkout step here.