fix: type annotations on ResourceManager.get_resource_manager

Signed-off-by: ixlmar <206748156+ixlmar@users.noreply.github.com>

Author: ixlmar

tensorrt_llm/_torch/pyexecutor/resource_manager.py

@@ -1300,8 +1300,9 @@ def register_resource_manager(self, name: str,
                                   resource_manager: BaseResourceManager):
         self.resource_managers[name] = resource_manager
 
-    def get_resource_manager(self, name: str) -> BaseResourceManager:
-        return self.resource_managers.get(name)
+    def get_resource_manager(
+            self, name: ResourceManagerType) -> Optional[BaseResourceManager]:
+        return self.resource_managers.get(name.value)
 
     @nvtx_range("prepare_resources")
     def prepare_resources(self, scheduled_batch: ScheduledRequests):