**Description**


It would be great if the metrics we publish in Airflow change to include TAGs for "variable" parts of those (such as dag_id, task_id, pool name) rather than being part of the metrics.

See here: https://airflow.apache.org/docs/1.10.12/metrics.html, https://airflow.readthedocs.io/en/latest/logging-monitoring/metrics.html  - those variable parts should be tags.

We might consider to change those metrics by default in 2.0 and possibly introduce a backport in 1.10.13 to allow people to migrate.


**Use case / motivation**

Having the variable parts of the metrics makes it really difficult to aggregate the metrics. Seems that statsd python library does not support tags, but there are possible solutions by installing extensions:

https://stackoverflow.com/questions/49852654/sending-statsd-metrics-with-tags-from-python-client

**Related Issues**

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from __future__ import annotations
import collections
import logging
import multiprocessing
import os
import pathlib
import random
import socket
import sys
import threading
from datetime import datetime, timedelta
from logging.config import dictConfig
from tempfile import TemporaryDirectory
from textwrap import dedent
from unittest import mock
from unittest.mock import MagicMock, PropertyMock
import pytest
import time_machine
from sqlalchemy import func
from airflow.callbacks.callback_requests import CallbackRequest, DagCallbackRequest, SlaCallbackRequest
from airflow.config_templates.airflow_local_settings import DEFAULT_LOGGING_CONFIG
from airflow.configuration import conf
from airflow.dag_processing.manager import (
    DagFileProcessorAgent,