feat(gateway): add instance ttl extension

- increase instance ttl extend threshold to 14 days

contracts/axelar-gateway/src/contract.rs

@@ -11,11 +11,11 @@ const CONTRACT_VERSION: &str = env!("CARGO_PKG_VERSION");
 
 /// Parameters for extending the contract instance and its instance storage.
 ///
-/// If the instance's time to live falls below 7 days, it will be extended by 60 days.
+/// If the instance's time to live falls below 14 days, it will be extended by 60 days.
 ///
-/// If at least one message is approved per week, the instance should never be archived.
+/// If at least one message is approved every 14 days, the instance should never be archived.
 const LEDGERS_PER_DAY: u32 = (24 * 3600) / 5;
-const INSTANCE_TTL_THRESHOLD: u32 = 7 * LEDGERS_PER_DAY;
+const INSTANCE_TTL_THRESHOLD: u32 = 14 * LEDGERS_PER_DAY;
 const INSTANCE_TTL_EXTEND_TO: u32 = 60 * LEDGERS_PER_DAY;
 
 #[contract]