[AIRFLOW-6706] Lazy load operator extra links (#7327)

[turbaszek]

closes: #10171

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[anitakar]

When I was thinking about it, I preserved the old serialization the old way and new serialization the new way. But adding old here is much better.

[turbaszek]

I tested it with:

# bq.py
from airflow.models import BaseOperatorLink


class BigQueryConsoleLink(BaseOperatorLink):
    name = 'BigQuery Console'

    def get_link(self, operator, dttm):
        return "teees"

and DAG:

class CustomOp(DummyOperator):
    @property
    def operator_extra_links(self):
        return (BigQueryConsoleLink(),)


with DAG("example_link",
    schedule_interval=None,  # Override to match your needs
    start_date=days_ago(1),
) as dag:
    task = CustomOp(task_id="task_withlink")

I added bq.BigQueryConsoleLink to BUILTIN_OPERATOR_EXTRA_LINKS and I see no atomic cloud <3

[potiuk]

LGTM

[potiuk]

SHll we un-draft and rerun it ?

[potiuk]

airflow/plugins_manager.py:118:1: E303 too many blank lines (3)