`invoke_and_assert` utility asserts on truncated output.

[bunchesofdonald]

First check

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Bug summary

When using the invoke_and_assert utility for testing the command line the content that's asserted against is a truncated version.

Reproduction

import pytest

from prefect import flow
from prefect.orion.schemas import states
from prefect.testing.cli import invoke_and_assert


@flow(name="hello")
def hello_flow():
    return "Hello!"


@pytest.fixture
async def scheduled_flow_run(orion_client):
    return await orion_client.create_flow_run(
        name="scheduled_flow_run", flow=hello_flow, state=states.Scheduled()
    )


def test_my_great_test(scheduled_flow_run):
    invoke_and_assert(
        command=["flow-run", "ls"],
        expected_output_contains=str(scheduled_flow_run.id),
        expected_code=0,
    )

Error

------ CLI output ------
                                   Flow Runs
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┳━━━┳━━━━━━━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━━━━┓
┃                               ID ┃ … ┃ Name           ┃ State ┃ When         ┃
┡━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━╇━━━━━━━━━━━━━━━━╇━━━━━━━╇━━━━━━━━━━━━━━┩
│ 46eadfd7-c9ea-4b7a-8342-26a10ed… │ … │ scheduled_flo… │ SCHE… │ a few secon… │
└──────────────────────────────────┴───┴────────────────┴───────┴──────────────┘

------ desired content ------
46eadfd7-c9ea-4b7a-8342-26a10ed65eca

Versions

Clean checkout of main.

Additional context

No response