Bug 2002305 - Fix record parsing in Nimbus (#7105)

Because we are no longer making HTTP requests to the Remote Settings
endpoint and are instead using the RemoteSettingsService in the SDK, we
are getting different data back -- we get the actual records themselves
instead of the HTTP payload that contains some metadata. This was
refactored incorrectly in
a2b2981
and broke experiment fetching.

Author: freshstrangemusic

components/nimbus/src/stateful/client/http_client.rs

@@ -31,11 +31,7 @@ impl SettingsClient for Arc<RemoteSettingsClient> {
         let records = self.get_records(true).ok_or(RemoteSettingsError::Other {
             reason: "Unable to fetch experiment records".to_owned(),
         })?;
-        let data_vec: Vec<_> = records
-            .into_iter()
-            .map(|r| r.fields.get("data").cloned())
-            .collect();
-        let wrapped_data = json!({ "data": data_vec });
+        let wrapped_data = json!({ "data": records });
         let resp = serde_json::to_string(&wrapped_data).map_err(|e| {
             NimbusError::JSONError(
                 "SettingsClient::fetch_experiments resp = serde_json::to_string".to_owned(),