Update Airnode address description

Author: serhhan

docs/oev-searchers/glossary.md

@@ -34,9 +34,7 @@ schema.
 
 ### Airnode address
 
-All [API providers](#api-provider) [sign their data](#signed-data) with an EOA
-wallet. The address of this wallet is announced by the respective API provider
-in the DNS records of the base URL of their API.
+All [API providers](#api-provider) [sign their data](#signed-data) with an EOA wallet. The authorized signing address is published at `https://signed-api.<api-provider-domain>` and announced via the `certifiedAirnodes` field in the returned JSON.
 
 ### Airnode feed