Create nodejs/actions repository

[avivkeller]

As the number of GitHub Actions across the Node.js organization grows, there's a significant amount of duplication and redundancy. For example, the same caritat actions are used in both the TSC and collaborator-public-votes repositories. Similarly, actions related to the website are shared between api-docs-tooling and nodejs.org.

To improve maintainability and promote reuse, I propose we create a new repository: nodejs/actions.

The nodejs/actions repository would serve as a central location for reusable GitHub Actions maintained by the Node.js organization. Each action would be stored in its own subdirectory and managed by the relevant team.

uses: nodejs/actions/web-infra/dependency-review
uses: nodejs/actions/caritat/closeVote

Each subdirectory would be controlled by a specific team via CODEOWNERS. For instance:

/web-infra/* @nodejs/web-infra
/*       @nodejs/actions

[avivkeller]

CC @nodejs/actions