Merge branch 'jc-docs-update-with-gitaly-logging' into 'master'

Update gitaly installation from source docs to add default logging values

See merge request gitlab-org/gitlab!18822

doc/administration/gitaly/index.md

@@ -222,6 +222,11 @@ Check the directory layout on your Gitaly server to be sure.
 
    [auth]
    token = 'abc123secret'
+
+   [logging]
+   format = 'json'
+   level = 'info'
+   dir = '/var/log/gitaly'
    ```
 
 1. Append the following to `/home/git/gitaly/config.toml` for each respective server: