sig-list.md: create postsubmit prow job that updates after changes to sigs.yaml

[dhiller]

Is your feature request related to a problem? Please describe:
Currently, whenever sigs.yaml is updated, sig-list.md (which is generated from sigs.yaml needs to get updated by calling:

make generate

Describe the solution you'd like:
A way that tells the user that they need to update sig-list.md by running the above command before the merge is completed.

Easiest might be a presubmit job that calls the target and checks whether the git state is clean.

Describe alternatives you've considered:
Variants of that might be:

• a postsubmit that is executed after changes to sigs.yaml or
• a periodic
  either way they call the target and create a pull request afterwards.

Additional context:

• example of an existing postsubmit for community sigs.yaml

/good-first-issue

[dhiller]

/area automation

[kubevirt-bot]

@dhiller: The label(s) area/automation cannot be applied, because the repository doesn't have them.

In response to this:

/area automation

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[dhiller]

/label good-first-issue

[kubevirt-bot]

@dhiller: Can not set label good-first-issue: Must be member in one of these teams: [kubevirtorg-label]

In response to this:

/label good-first-issue

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.