Confirm / Update UIKit Contribution Guidelines and Testing Steps

[sghoweri]

Related to the UIkit PR discussion here, I’d like to make sure these contribution guidelines and/or these contribution docs are up to date with step by step testing instructions we should be running through when reviewing or PRing frontend updates to Pattern Lab Node.

[stale]

It's hard to keep track of everything. This issue has been automatically marked as stale because it has not had recent activity, neither from the team nor the community. It will be closed if no further activity occurs. Please consider adding additional info, volunteering to contribute a fix for this issue, or making a further case that this is important to you, the team, and the project as a whole. Thanks!

[stale]

Issue closed after going stale. It can be re-opened if still relevant.

[stale]

Issue closed after going stale. It can be re-opened if still relevant.

[stale]

Issue closed after going stale. It can be re-opened if still relevant.