Add json kwarg to [Async]Client.post()

[MrCreosote]

Allows using the clients to call the callback endpoint in the Superfacility beta API.

Closes #87

Manual testing:

~/github/mrcreosote/sfapi_client$ ipython
Python 3.11.3 (main, Apr  5 2023, 14:14:40) [GCC 7.5.0]
Type 'copyright', 'credits' or 'license' for more information
IPython 8.27.0 -- An enhanced Interactive Python. Type '?' for help.

In [3]: from sfapi_client import AsyncClient, Client
f
In [4]: from sfapi_client.compute import Machine

In [5]: beta_url="https://api.nersc.gov/api/beta"

In [6]: async with AsyncClient(client_id=nersc_client_id, secret=nersc_private_k
   ...: ey) as cli:
   ...:     pm = await cli.compute(Machine.perlmutter)
   ...:     ret = await pm.run("ls ~")
   ...:     print(ret)
   ...:
cdm
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mash
minio
tmp

In [7]: with Client(client_id=nersc_client_id, secret=nersc_private_key) as cli:
   ...:
   ...:     pm = cli.compute(Machine.perlmutter)
   ...:     ret = pm.run("ls ~")
   ...:     print(ret)
   ...:
cdm
dots
Downloads
github
mash
minio
tmp

In [8]: async with AsyncClient(api_base_url=beta_url, client_id=nersc_client_id,
   ...:  secret=nersc_private_key) as cli:
   ...:     ret = await cli.post("callback/", json={
   ...:         "timeout": 10,
   ...:         "path_condition": {
   ...:             "path": "~/foo",
   ...:             "machine": "perlmutter",
   ...:         },
   ...:         "url": "https://teletubbiessuperfans.com/signup",
   ...:     })
   ...:     print(ret.json())
   ...:
{'timeout': 10, 'path_condition': {'path': '~/foo', 'machine':
'perlmutter'}, 'url': 'https://teletubbiessuperfans.com/signup'}

In [9]: with Client(api_base_url=beta_url, client_id=nersc_client_id, secret=ner
   ...: sc_private_key) as cli:
   ...:     ret = cli.post("callback/", json={
   ...:         "timeout": 10,
   ...:         "path_condition": {
   ...:             "path": "~/foo",
   ...:             "machine": "perlmutter",
   ...:         },
   ...:         "url": "https://teletubbiessuperfans.com/signup",
   ...:     })
   ...:     print(ret.json())
   ...:
{'timeout': 10, 'path_condition': {'path': '~/foo', 'machine': 
'perlmutter'}, 'url': 'https://teletubbiessuperfans.com/signup'}

[cjh1]

Thanks for taking the time to push these changes. For future reference the whole _sync directory is actually generate from the _async directory. So you can just make the changes in _async and then run python scripts/run.py unasync ( you may find more missing deps! ) and the _sync dir will be updated.