service/vault: fix links

service/vault.md

 The vault service, based on [Vaultwarden][], serves as a secrets storage
 application.
 
-Vaultwarden: https://github.com/dani-garcia/vaultwarden
+[Vaultwarden]: https://github.com/dani-garcia/vaultwarden
 
 [[_TOC_]]
 
@@ -45,7 +45,7 @@ Vaultwarden: https://github.com/dani-garcia/vaultwarden
 ## 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: