doc: Update gitaly team onboarding instructions (!5703) · Merge requests · GitLab.org / gitaly · GitLab

Andras Horvath requested to merge ahorvath-onboarding-20230427 into master Apr 27, 2023

Add reference to new google group https://gitlab.com/gitlab-com/team-member-epics/access-requests/-/issues/21356#note_1368985234
Cc: @jcaigitlab on onboarding issues

Issue https://gitlab.com/gitlab-com/team-member-epics/access-requests/-/issues/21356