Move Listeners into airflow_shared module

[amoghrajesh]

Body

Ref: https://github.com/apache/airflow/tree/main/airflow-core/src/airflow/listeners

Used across core, sdk, and some providers too

Committer

• I acknowledge that I am a maintainer/committer of the Apache Airflow project.

[rawwar]

@amoghrajesh , shall I work on this?

[amoghrajesh]

Assigning it to you @rawwar. Feel free to ping me to have a chat about this before you start

[rawwar]

i'm about to go on a vacation. So, unassigning it for now