Add markdown check action

[nvliyuan]

add github action to check broken markdown links on dev-branch 22.04
related to #4906

[nvliyuan]

please found the detail information about this pr in #4906

[pxLi]

# Copyright (c) 2022, NVIDIA CORPORATION.

[nvliyuan]

thanks, updated

[pxLi]

pull_request_target -> pull_request to checkout the "refs/pull/:prNumber/merge"
otherwise the
- uses: actions/checkout@master
will check out the BASE ref here (branch-22.04)

FYI we use pull_request_target in signoff-check is only because that the check is based on BASE branch instead of relying on developer's feature branch

[nvliyuan]

thanks and good to know that, one question is that do we need a GITHUB_TOKEN when we use pull_request ?
If we don't add a GITHUB_TOKEN, will we hit Error: Parameter token or opts.auth is required?

[pxLi]

GITHUB_TOKEN is the default token of repo and is maintained by github action itself as ENV.

If we don't add a GITHUB_TOKEN, will we hit Error: Parameter token or opts.auth is required?

For actions/checkout, no.
I am not sure where you did get this error, if the some specific action require adding specific arg, then you can try add

      with:
        token: ${{ secrets.GITHUB_TOKEN }}

above was just an example, this really arg naming depends on the action provider, if they require extra tokens (or access), they should have documented somewhere in their repo

[pxLi]

after changing to pull_request, you can see result in this PR's check status

[pxLi]

LGTM. Let's merge this first and let it run for several days before marking it as a required check

[pxLi]

build