allow for "releases only" mode and may be RF specification for the paths?

[yarikoptic]

I wanted to test my ability to RTFM into its details on either I need to specify type_id to place releases into subfolders so came up with this

repo: datalad/git-annex
vars:
  common_path: 'builds/{year}/{month}//{type}-{type_id[:8]}/{wf_file}-{number}-{build_commit[:8]}-{common_status}/'
ci:
  github:
    # only releases
    releases_path: 'releases/{type_id}'
    workflows:
    - build-macos.yaml
    - build-ubuntu.yaml
    - build-windows.yaml
since: 2021-03-01T00:00:00Z
types: []

config but running it crashed with

Traceback (most recent call last):
  File "/home/datalad/miniconda3/envs/tinuous-dev/bin/tinuous", line 33, in <module>
    sys.exit(load_entry_point('tinuous', 'console_scripts', 'tinuous')())
  File "/home/datalad/miniconda3/envs/tinuous-dev/lib/python3.9/site-packages/click/core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "/home/datalad/miniconda3/envs/tinuous-dev/lib/python3.9/site-packages/click/core.py", line 782, in main
    rv = self.invoke(ctx)
  File "/home/datalad/miniconda3/envs/tinuous-dev/lib/python3.9/site-packages/click/core.py", line 1256, in invoke
    Command.invoke(self, ctx)
  File "/home/datalad/miniconda3/envs/tinuous-dev/lib/python3.9/site-packages/click/core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/datalad/miniconda3/envs/tinuous-dev/lib/python3.9/site-packages/click/core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "/home/datalad/miniconda3/envs/tinuous-dev/lib/python3.9/site-packages/click/decorators.py", line 21, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/mnt/datasets/datalad/ci/tinuous/src/tinuous/__main__.py", line 60, in main
    ctx.obj = Config.parse_obj(safe_load(fp))
  File "pydantic/main.py", line 578, in pydantic.main.BaseModel.parse_obj
  File "pydantic/main.py", line 406, in pydantic.main.BaseModel.__init__
pydantic.error_wrappers.ValidationError: 1 validation error for Config
ci -> github -> path
  field required (type=value_error.missing)

suggesting that path (for logs) is mandatory. Now that we have different paths and ppl might want or not download just releases or just artifacts, I think we should allow for path to be optional.

I even wonder if it would be worthwhile to RF into

paths:
  logs:
  artifacts:
  releases:

to make specification cleaner (good that we don't have yet too many deployments to adjust config for ;))