**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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self, session: Session = NEW_SESSION, execute_callbacks: bool = True
    ) -> tuple[list[TI], DagCallbackRequest | None]:
        """
        Determines the overall state of the DagRun based on the state
        of its TaskInstances.
        :param session: Sqlalchemy ORM Session
        :param execute_callbacks: Should dag callbacks (success/failure, SLA etc.) be invoked
            directly (default: true) or recorded as a pending request in the ``returned_callback`` property
        :return: Tuple containing tis that can be scheduled in the current loop & `returned_callback` that
            needs to be executed
        """
        
        callback: DagCallbackRequest | None = None
        class _UnfinishedStates(NamedTuple):
            tis: Sequence[TI]
            @classmethod
            def calculate(cls, unfinished_tis: Sequence[TI]) -> _UnfinishedStates:
                return cls(tis=unfinished_tis)
            @property
            def should_schedule(self) -> bool: