site-root: add Gerrit Code Review Logo

Gerrit Code Review is an open-source,  web-based code review tool
built on Git. The project started over 15 years ago and is the used as
version control tool of choice for many open source projects like
Chromium and Android.

The Gerrit community has also hugely developped JGit, the
java implementation of Git.

Author: DanieleSassoli

layouts/partials/site-root.html

@@ -69,6 +69,7 @@ <h3 class="text-center">Products providing Git hosting</h3>
     (dict "name" "gitea" "url" "https://gitea.com")
     (dict "name" "tangled" "url" "https://tangled.sh")
     (dict "name" "radicle" "url" "https://radicle.xyz")
+    (dict "name" "gerrit" "url" "https://www.gerritcodereview.com")
     }}
     {{ range shuffle $m }}
     <li><a href="{{ .url }}">{{ partial "company-svg" (printf "company-project-logos/%s" .name) }}</a></li>