Increase lambda splay by 4x (#43114)

GitOrigin-RevId: 597c4c62b04998a8bae9abecd536b5a4421431a0

Author: emmaling27

crates/common/src/knobs.rs

@@ -1070,7 +1070,7 @@ pub static FUNRUN_INITIAL_PERMIT_TIMEOUT: LazyLock<Duration> =
 ///
 /// You can check go/num-instances-with-lambdas
 pub static AWS_LAMBDA_DEPLOY_SPLAY: LazyLock<Duration> =
-    LazyLock::new(|| Duration::from_secs(env_config("AWS_LAMBDA_DEPLOY_SPLAY_SECONDS", 5000)));
+    LazyLock::new(|| Duration::from_secs(env_config("AWS_LAMBDA_DEPLOY_SPLAY_SECONDS", 20000)));
 
 /// How long of a window to debounce static lambda deployments. Don't allow too
 /// many static deploys in a small window to protect the infrastructure.