Merge branch 'eread/minor-updates-to-gitaly-dev-docs' into 'master'

Minor updated to Gitaly development documentation

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/184425



Merged-by: Roshni Sarangadharan <rsarangadharan@gitlab.com>
Co-authored-by: Evan Read <eread@gitlab.com>