style(cli): re-fmt one stray format! line in the integration test

A trailing fmt drift on tests/cli.rs:95 — `format!()` arg was wrapped
across three lines where rustfmt wants one. Running `cargo fmt --all`
collapses it; no behavior change.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/picloud-cli/tests/cli.rs

@@ -95,9 +95,7 @@ fn run_flow(url: &str) {
         .args(["login"])
         .assert()
         .success()
-        .stdout(predicate::str::contains(format!(
-            "Logged in as {username}"
-        )));
+        .stdout(predicate::str::contains(format!("Logged in as {username}")));
 
     let creds_path = env.config_dir.join("credentials");
     assert!(