Allow overlaying the DNS probe timeout.

Test: m
Bug: 129312219
Change-Id: I84461d40e4d2e63ce8c111c047cbc085cb49443e
diff --git a/packages/NetworkStack/res/values/overlayable.xml b/packages/NetworkStack/res/values/overlayable.xml
index 23b8de6..b9d5337 100644
--- a/packages/NetworkStack/res/values/overlayable.xml
+++ b/packages/NetworkStack/res/values/overlayable.xml
@@ -17,6 +17,7 @@
     <overlayable name="NetworkStackConfig">
         <policy type="product|system|vendor">
             <!-- Configuration values for NetworkMonitor -->
+            <item type="integer" name="config_captive_portal_dns_probe_timeout"/>
             <item type="string" name="config_captive_portal_http_url"/>
             <item type="string" name="config_captive_portal_https_url"/>
             <item type="array" name="config_captive_portal_fallback_urls"/>