Can we enable shallow cloning?

## Describe Request:
The code checkout step of this orb is the vast majority of the build time for this step in our CircleCI workflow. Shallow checkout (ie: using `git clone --depth=1` would cut this step's duration by roughly 75% for our monolith codebase
## Examples:
I don't know enough about how this orb works to provide code examples, but I _may_ be willing to learn if it's not too involved
## Supporting Documentation Links:
Here's our current task that uses this orb:

We use this `shallow_checkout` orb (https://circleci.com/developer/orbs/orb/datacamp/shallow-checkout) for the following steps of this build, and it routinely runs the code checkout step in 9-10 seconds, which would be a great benefit to speed up our builds a bit

The issue identifies the orb's code checkout step but names no file or test. Start by tracing the checkout implementation and any existing workflow checks in the repository; done means the orb supports the requested shallow checkout behavior without breaking its current checkout flow.

Written by the indexing model from the issue text.