docs: add referringConnector claim to initial deployment documentation

README.md

@@ -1,4 +1,4 @@
-<!-- Improved compatibility of back to top link: See: https://github.com/othneildrew/Best-README-Template/pull/73 -->
+v<!-- Improved compatibility of back to top link: See: https://github.com/othneildrew/Best-README-Template/pull/73 -->
 
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@@ -157,6 +157,9 @@ For that you will need a SKI/AKI ClientID. Please refer
 to [edc-extension's Getting Started Guide](https://github.com/sovity/edc-extensions/tree/main/docs/getting-started#faq)
 on how to generate one.
 
+The DAPS needs to contain the claim `referringConnector=broker` for the broker.
+The expected value `broker` could be overridden by specifying a different value for `MY_EDC_PARTICIPANT_ID`.
+
 ```yaml
 # Required: Fully Qualified Domain Name
 MY_EDC_FQDN: "example.com"