RRule should be a JSON string rather than rrule string

[anna-geller]

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Bug summary

The fix applied to "build CLI" from #6761 should also be applied to "set-schedule" CLI:

prefect deployment set-schedule flow/deployment \
--rrule '''{"rrule": "DTSTART:20220921T110000\nRRULE:FREQ=DAILY;COUNT=7;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9", "timezone": "Europe/Berlin"}'

Otherwise, any rule that has a start date (DTSTART), e.g.:

prefect deployment set-schedule healthcheck/prod --timezone 'Europe/Berlin' \
--rrule 'DTSTART:20220921T110000\nRRULE:FREQ=DAILY;COUNT=7;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9'

will raise the same RRule ValidationError as in #6739

cc @anticorrelator

Error

Traceback (most recent call last):
  File "/opt/miniconda3/envs/201/lib/python3.9/site-packages/prefect/cli/_utilities.py", line 41, in wrapper
    return fn(*args, **kwargs)
  File "/opt/miniconda3/envs/201/lib/python3.9/site-packages/prefect/utilities/asyncutils.py", line 212, in wrapper
    return run_async_in_new_loop(async_fn, *args, **kwargs)
  File "/opt/miniconda3/envs/201/lib/python3.9/site-packages/prefect/utilities/asyncutils.py", line 141, in run_async_in_new_loop
    return anyio.run(partial(__fn, *args, **kwargs))
  File "/opt/miniconda3/envs/201/lib/python3.9/site-packages/anyio/_core/_eventloop.py", line 70, in run
    return asynclib.run(func, *args, **backend_options)
  File "/opt/miniconda3/envs/201/lib/python3.9/site-packages/anyio/_backends/_asyncio.py", line 292, in run
    return native_run(wrapper(), debug=debug)
  File "/opt/miniconda3/envs/201/lib/python3.9/asyncio/runners.py", line 44, in run
    return loop.run_until_complete(main)
  File "/opt/miniconda3/envs/201/lib/python3.9/asyncio/base_events.py", line 647, in run_until_complete
    return future.result()
  File "/opt/miniconda3/envs/201/lib/python3.9/site-packages/anyio/_backends/_asyncio.py", line 287, in wrapper
    return await func(*args)
  File "/opt/miniconda3/envs/201/lib/python3.9/site-packages/prefect/cli/deployment.py", line 226, in set_schedule
    await client.update_deployment(deployment, schedule=updated_schedule)
  File "/opt/miniconda3/envs/201/lib/python3.9/site-packages/prefect/client.py", line 1385, in update_deployment
    deployment_create = schemas.actions.DeploymentUpdate(
  File "pydantic/main.py", line 341, in pydantic.main.BaseModel.__init__
pydantic.error_wrappers.ValidationError: 5 validation errors for DeploymentUpdate
schedule -> interval
  field required (type=value_error.missing)
schedule -> rrule
  extra fields not permitted (type=value_error.extra)
schedule -> cron
  field required (type=value_error.missing)
schedule -> rrule
  extra fields not permitted (type=value_error.extra)
schedule -> rrule
  Invalid RRule string "DTSTART:20220921T110000\nRRULE:FREQ=DAILY;COUNT=7;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9": Unknown string format: 20220921T110000\NRRULE:FREQ=DAILY;COUNT=7;BYDAY=MO (type=value_error)
An exception occurred.

Versions

Version:             2.4.0
API version:         0.8.0
Python version:      3.9.12
Git commit:          513639e8
Built:               Tue, Sep 13, 2022 2:15 PM
OS/Arch:             darwin/arm64
Profile:             dev
Server type:         cloud