[write_standby]: Increase timeout to 60s (#10065)

- Avoid scenarios where script times out before orchagent can establish IPinIP tunnel

Signed-off-by: Lawrence Lee <lawlee@microsoft.com>

files/scripts/write_standby.py

@@ -91,7 +91,7 @@ class MuxStateWriter(object):
         tunnel_key_pattern = 'ASIC_STATE:SAI_OBJECT_TYPE_TUNNEL:*'
         return len(self.asic_db.keys('ASIC_DB', tunnel_key_pattern)) > 0
 
-    def wait_for_tunnel(self, interval=1, timeout=30):
+    def wait_for_tunnel(self, interval=1, timeout=60):
         """
         Waits until the IP-in-IP tunnel has been created