build: upgrade to node20

[lampajr]

Hi team 👋,
We are using this action as part of some of our projects and we started noticing the warning below, that's why I created this PR.

Description

Upgrade the node versio that will be used by the action at runtime.

Motivation and Context

GitHub started warning actions running on node16:

[run](https://github.com/Hyperfoil/Horreum/actions/runs/8214138182/job/22466298403)
Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: wow-actions/welcome@v1. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Enhancement (changes that improvement of current feature or performance)
• Refactoring (changes that neither fixes a bug nor adds a feature)
• Test Case (changes that add missing tests or correct existing tests)
• Code style optimization (changes that do not affect the meaning of the code)
• Docs (changes that only update documentation)
• Chore (changes that don't modify src or test files)

Self Check before Merge

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[lampajr]

Hey @bubkoo, sorry to bother you and I hope you are the right person to tag here!
Is there any chance to get this in?

[Piedone]

I just bumped into this. This action is really the best for this task (and much better than the official actions/first-interaction), so it would be great to have this fixed. It seems like a very simple fix, the action just works with Node 20 too. I forked this repo for Orchard Core too, for this: OrchardCMS/OrchardCore#15708.