All inputs should have descriptions

[jameslamb]

Description

Workflow inputs can have a description:

shared-workflows/.github/workflows/conda-cpp-build.yaml

Lines 19 to 22 in c802825

	script:
	type: string
	required: true
	description: "Shell code to be executed in a step. Ideally this should just invoke a script managed in the repo the workflow runs from, like 'ci/build_cpp.sh'."

Every input here should have one.

Benefits of this work

• makes it easier to understand the workflow files when you're reading them (for example, when configuring a new use of them in a repo)
• makes it easier to choose useful values when triggering with workflow_dispatch in the UI (descriptions show up there)

Acceptance Criteria

• all inputs to the main RAPIDS workflows have informative descriptions

Approach

Add input descriptions for all of the workflows in this repo.

For longer notes, wrap like this:

shared-workflows/.github/workflows/conda-python-build.yaml

Lines 34 to 37 in c802825

	description: |
	If provided, should contain the name of a secret in the repo which holds a GitHub API token.
	When this is non-empty, that secret's value is used in place of the default repo-level token
	anywhere that environment variable GH_TOKEN is set.

Add descriptions at the callsites for these workflows across RAPIDS as well, for example:

https://github.com/rapidsai/cudf/blob/3e357c708d462b1df93b55a963d9e04973455da3/.github/workflows/build.yaml#L9-L22

• cucim (add docs on CI workflow inputs cucim#897)
• cudf (add docs on CI workflow inputs cudf#19234)
• cugraph (add docs on CI workflow inputs cugraph#5139)
• cugraph-docs (add docs on CI workflow inputs cugraph-docs#137)
• cugraph-gnn (add docs on CI workflow inputs cugraph-gnn#235)
• cuml (add docs on CI workflow inputs cuml#6952)
• cumlprims_mg (https://github.com/rapidsai/cumlprims_mg-private/pull/268)
• cuvs (add docs on CI workflow inputs cuvs#1075)
• cuxfilter (add docs on CI workflow inputs cuxfilter#706)
• dask-cuda (add docs on CI workflow inputs dask-cuda#1515)
• integration (add docs on CI workflow inputs integration#779)
• jupyterlab-nvdashboard (add docs on CI workflow inputs jupyterlab-nvdashboard#239)
• kvikio (add docs on CI workflow inputs kvikio#764)
• nx-cugraph (add docs on CI workflow inputs nx-cugraph#164)
• pynvjitlink (no changes required)
• raft (add docs on CI workflow inputs raft#2728)
• rapids-cmake (add docs on CI workflow inputs rapids-cmake#868)
• rapids-dask-dependency (add docs on CI workflow inputs rapids-dask-dependency#113)
• rapidsmpf (add docs on CI workflow inputs rapidsmpf#368)
• rmm (add docs on CI workflow inputs rmm#1975)
• ucx-py (add docs on CI workflow inputs ucx-py#1150)
• ucxx (add docs on CI workflow inputs ucxx#450)

Notes

Inspired by a recent discussion with @jakirkham , where we observed it requiring a couple of failed attempts to figure out the correct values to supply when manually re-triggering nightly test jobs.