feat: add labels input to configure

[NotFounds]

It would be cool to attach labels when the action creates a release PR.
For example, if we add a release label to PRs, we can find release PRs easily.

I implemented labels input.
labels allows input, and we can specify comma-separated labels(include space).

e.g.

      - name: Create Release Pull Request
        uses: notfounds/changesets-action@main
        with:
          publish: yarn changeset publish
          labels: "release,test label,test-label2"

cf. https://github.com/NotFounds/changesets-monorepo/blob/d42f07d8b7def90913c71be14e9d69c8d3254876/.github/workflows/release.yml

I confirmed it works well in NotFounds/changesets-monorepo#5.

[changeset-bot]

🦋 Changeset detected

Latest commit: a614ab5

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@changesets/action	Minor

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[NotFounds]

@Andarist
Hi, Could you review this or assign a reviewer, please?

[alstn2468]

LGTM

[jimmynXD]

is this available yet????

[Andarist]

I think this would be better as a separate action that could label PRs based on the input. This way you could provide the output of this action to that labeling action and we could include an example like that in our docs. I don't see a strong reason to include this new input here when this is easily achievable through composition.

[Andarist]

I've created a PR here that should help to solve this need through composition.