flow_run_name formatting variable does not work in task run logger

[leonarduschen]

First check

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Bug summary

The variable flow_run_name in task_run_logger replaced with <unknown> instead of the actual flow run name

Reproduction

Change the following part of https://github.com/PrefectHQ/prefect/blob/2.8.2/src/prefect/logging/logging.yml and copy to ~/.prefect/logging.yml

task_run_fmt: "%(asctime)s.%(msecs)03d | %(levelname)-7s | Flow run %(flow_run_name)r - Task run %(task_run_name)r - %(message)s"

Flow code snippet:

from prefect import flow, get_run_logger, task
from prefect.context import get_run_context


@task
def say_hello_world() -> None:
    logger = get_run_logger()
    logger.info("Hello World")


@flow(name="hello-world")
def main_flow() -> None:
    logger = get_run_logger()

    flow_context = get_run_context()

    logger.info(f"Running flow at {flow_context.start_time}")

    say_hello_world()


if __name__ == "__main__":
    main_flow()

Error

15:37:42.607 | INFO    | prefect.engine - Created flow run 'beautiful-chicken' for flow 'hello-world'
15:37:42.707 | INFO    | Flow run 'beautiful-chicken' - Running flow at 2023-02-22T07:37:42.706671+00:00
15:37:42.736 | INFO    | Flow run 'beautiful-chicken' - Created task run 'say_hello_world-0' for task 'say_hello_world'
15:37:42.737 | INFO    | Flow run 'beautiful-chicken' - Executing 'say_hello_world-0' immediately...
15:37:42.774 | INFO    | Flow run 'beautiful-chicken' - Task run 'say_hello_world-0' - Hello World
15:37:42.798 | INFO    | Flow run '<unknown>' - Task run 'say_hello_world-0' - Finished in state Completed()
15:37:42.827 | INFO    | Flow run 'beautiful-chicken' - Finished in state Completed('All states completed.')

Versions

Version:             2.8.2
API version:         0.8.4
Python version:      3.9.7
Git commit:          afbed19d
Built:               Fri, Feb 17, 2023 10:02 AM
OS/Arch:             linux/x86_64
Profile:             default
Server type:         server

Additional context

No response

[leonarduschen]

@EmilRex