chore(ci): Speed up deploy step with shallow checkout

[adamharvey-okta]

This PR speeds up the deploy step in CI by performing a shallow checkout. I noticed it was taking ~3 minutes for every PR and production deploys off mainline. This should help both improve performance of the pipeline, as well as (slightly) reduce compute credit consumption in CircleCI. Supports OKTA-728901.

For the Cypress jobs, the checkout is built in and that'll need a different workaround.

Before	After

From 2 minutes 43 seconds to checkout, to 25 seconds. (roughly)

Useful references:

• https://support.circleci.com/hc/en-us/articles/360045096514-Shallow-Repository-Cloning
• https://github.blog/2020-12-21-get-up-to-speed-with-partial-clone-and-shallow-clone/