Prefill form values for hand raise leads

What does this MR do and why?

Prefill form values for hand-raise leads

Related to #334211 (closed) Also related to #342698 (closed) for provide/inject

Screenshots or screen recordings

handraisepql3-2021-10-19_18.19.36

How to set up and validate locally

1. Create a gitlab.com like GDK by making com? return true in lib/gitlab.rb
2. Enable feature flag

Feature.enable(:in_app_hand_raise_pql)

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.