Upgrade Gitaly server verion

icu4c had another version bump, which broken compilation of the native
extensions of charlock_holmes. Gitaly has upgraded the gem version, and
with this made installation against the new lib version, 61.1, available
again.

GITALY_SERVER_VERSION

-0.92.0
+0.93.0

changelogs/unreleased/zj-bump-gitaly.yml

+---
+title: Upgrade Gitaly to upgrade its charlock_holmes
+merge_request:
+author:
+type: other