xtask: Increase VM SSH timeout

The CoP tests have been failing a lot while waiting for SSH. It's
unclear if a longer timeout will help, but let's try it and see.

BUG=none
TEST=cargo xtask check

Change-Id: I509432a5dcdab909d8be98e60bd1448b14d52ec8
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crdyboot/+/5756149
Auto-Submit: Nicholas Bishop <nicholasbishop@google.com>
Commit-Queue: Steve Kendall <skend@google.com>
Tested-by: chromeos-cop-builder@chromeos-cop.iam.gserviceaccount.com <chromeos-cop-builder@chromeos-cop.iam.gserviceaccount.com>
Commit-Queue: Nicholas Bishop <nicholasbishop@google.com>
Tested-by: Nicholas Bishop <nicholasbishop@google.com>
Reviewed-by: Steve Kendall <skend@google.com>
diff --git a/xtask/src/vm_test.rs b/xtask/src/vm_test.rs
index a52b093..e1bf94a 100644
--- a/xtask/src/vm_test.rs
+++ b/xtask/src/vm_test.rs
@@ -34,7 +34,7 @@
 const VM_TIMEOUT_SHORT: Duration = Duration::from_secs(30);
 
 /// Timeout used for tests that need to wait for SSH.
-const VM_TIMEOUT_LONG: Duration = Duration::from_secs(180);
+const VM_TIMEOUT_LONG: Duration = Duration::from_secs(240);
 
 /// Download the well-known testing_rsa key for ChromeOS test images.
 fn download_test_key(conf: &Config) -> Result<()> {