Cannot set `operator_extra_links` in Operator `__init__` method for dynamically-mapped Tasks

### Apache Airflow version `main` ### If "Other Airflow 2 version" selected, which one? _No response_ ### What happened? When attempting to set `operator_extra_links` in the `__init__` method of an Operator, a button routing to that link will be properly displayed and functional. However, this is not the case when using dynamically mapped Tasks. **Attempting to set `extra_operator_links` in the `__init__` method of an Operator that is eventually "dynamically-mapped" fails to render the button for each mapped Task instance.** ### What you think should happen instead? When `operator_extra_links` are set in the `__init__` method of an Operator, the corresponding button should be rendered in the "Details" tab of each mapped Task instance. ### How to reproduce I tested the following, with the noted results for each. Throughout the testing process, I used the following code for my `CustomLink` and `AirflowExtraLinkPlugin` in the `plugins/operator_link.py` file, and my DAG code. ### CustomLink and AirflowExtraLinkPlugin ```python from airflow.sdk.bases.operatorlink import BaseOperatorLink from airflow.plugins_manager import AirflowPlugin class CustomLink(BaseOperatorLink): name: str = "CustomLink" def get_link(self, operator, *, ti_key) -> str: return "https://www.google.com" class AirflowExtraLinkPlugin(AirflowPlugin): name = "airflow_extra_link_plugin" operator_extra_links = [CustomLink(),] ``` ### DAG Code ```python from airflow.sdk import DAG from datetime import datetime from include.operators import CustomOperator with DAG( dag_id="try_extra_links", start_date=datetime(2020, 1, 1), schedule="@once" ) as dag: custom_operator = CustomOperator( task_id="custom_operator", value=1 ) custom_operator__mapped = CustomOperator.partial( task_id="custom_operator__mapped" ).expand(value=[1, 2, 3]) custom_operator >> custom_operator__mapped ``` ### operator_extra_links set at the Class-level ✅ …