Add instructions on how to debug zap
What does this MR do?
Documents instructions on how to compile ZAP, incorporate it into the DAST Docker image, and debug ZAP during a DAST scan using a remote Java debugger.
What are the relevant issue numbers?
Added as a way to get to the bottom of certificate errors outlined in https://gitlab.com/gitlab-org/gitlab/-/issues/371793.
Edited by Cameron Swords