service/vault: readd podman link

service/vault.md

@@ -45,7 +45,7 @@ application.
 ## Installation
 
 This service is installed using the upstream-provided container which runs under
-Podman.
+[Podman][].
 
 To set it up, deploy the `profile::vaultwarden` Puppet profile. This will:
 
@@ -62,6 +62,8 @@ To set it up, deploy the `profile::vaultwarden` Puppet profile. This will:
 The installation requirements are recorded in the GitLab ticket:
 https://gitlab.torproject.org/tpo/tpa/team/-/issues/41541
 
+[Podman]: https://podman.io/
+
 ## Upgrades
 
 Because the cintainer is started with label `io.containers.autoupdate=registry`