NIFI-13379 Replaced use of deprecated com.nimbusds.oauth2.sdk.http.HT…

…TPResponse method getContentAsJSONObject with API suggested replacement getBodyAsJSONObject.

This closes apache#8944

Signed-off-by: Mike Thomsen <mthomsen@apache.org>

nifi-registry/nifi-registry-core/nifi-registry-web-api/src/main/java/org/apache/nifi/registry/web/security/authentication/oidc/StandardOidcIdentityProvider.java

@@ -255,7 +255,7 @@ private OIDCProviderMetadata retrieveOidcProviderMetadata(final String discovery
             throw new IOException("Unable to download OpenId Connect Provider metadata from " + url + ": Status code " + httpResponse.getStatusCode());
         }
 
-        final JSONObject jsonObject = httpResponse.getContentAsJSONObject();
+        final JSONObject jsonObject = httpResponse.getBodyAsJSONObject();
         return OIDCProviderMetadata.parse(jsonObject);
     }