DevTools: Improve resource_available to handle multiple connections (#36933)

This patch improves the `resource_available` trait to handle multiple
connections. In this patch we also remove the redundant
`resource_available` from worker actor

Testing: Existing tests in DevTools already tests for this. We do not
need to add new test
Fixes: part of #36027

Signed-off-by: atbrakhi <atbrakhi@igalia.com>
Co-authored-by: Delan Azabani <dazabani@igalia.com>

components/devtools/actors/browsing_context.rs

@@ -149,10 +149,6 @@ impl ResourceAvailable for BrowsingContextActor {
     fn actor_name(&self) -> String {
         self.name.clone()
     }
-
-    fn get_streams(&self) -> &RefCell<HashMap<StreamId, TcpStream>> {
-        &self.streams
-    }
 }
 
 impl Actor for BrowsingContextActor {