fix(#3422): give bridge-created identities an email too

#3414 fixed the missing-email defect in swarmctl only, so every identity
created by the bridge landed in users.yml with no `email`. A relying
party that asks for the claim does not degrade, it fails -- grafana's
OIDC login is the measured case (#3393).

Two writers of one file disagreeing about a field one of them treats as
required is not a difference worth keeping, and with the file shared the
result also depended on which tool wrote last.

Mutation-checked: removing the fill turns the new test red and nothing
else.

swarm-authelia-bridge/src/main.rs

@@ -278,7 +278,7 @@ async fn handle(state: &AppState, name: String) -> Result<BridgeResponse> {
             extra: std::collections::BTreeMap::new(),
         },
     );
-    store::publish(&cfg.users_file, &user_store)?;
+    store::publish(&cfg.users_file, &mut user_store)?;
     tracing::info!(agent = %name, "created authelia identity");
     Ok(BridgeResponse::Created)
 }