docs: update action from node16 to node20

Documentation changes to update action from node16 to node20

CHANGELOG.md

@@ -6,6 +6,7 @@ See [Releases](https://github.com/cypress-io/github-action/releases) for full de
 
 | Version | Changes                                                                                                                              |
 | ------- | ------------------------------------------------------------------------------------------------------------------------------------ |
+| v6.0.0  | Action runs under Node.js 20 instead of Node.js 16.                                                                                  |
 | v5.8.1  | Examples remove Node.js 19. End of support for Node.js 19.                                                                           |
 | v5.8.0  | Add GitHub step output `resultsUrl`. Deprecate `dashboardUrl`.                                                                       |
 | v5.7.0  | Add basic Yarn Modern Plug'n'Play support.                                                                                           |

README.md

@@ -1501,7 +1501,7 @@ jobs:
 
 ### Support
 
-Node.js is required to run this action. The current version `v5` supports:
+Node.js is required to run this action. The currently recommended version `v5` supports:
 
 - **Node.js** 16.x
 - **Node.js** 18.x
@@ -1515,15 +1515,16 @@ and is generally aligned with [Node.js's release schedule](https://github.com/no
 
 [![Node versions example](https://github.com/cypress-io/github-action/workflows/example-node-versions/badge.svg?branch=master)](.github/workflows/example-node-versions.yml)
 
-Cypress itself runs with a fixed Node.js version specified by the [runs.using](https://docs.github.com/en/actions/creating-actions/metadata-syntax-for-github-actions#runs-for-javascript-actions) parameter of [action.yml](action.yml). For `github-action@v5` this is `node16`.
+Cypress itself runs with a fixed Node.js version specified by the [runs.using](https://docs.github.com/en/actions/creating-actions/metadata-syntax-for-github-actions#runs-for-javascript-actions) parameter of [action.yml](action.yml). `github-action@v5` uses `node16` and `github-action@v5` uses `node20`.
 
 ## Changelog
 
 View the [CHANGELOG](./CHANGELOG.md) document for an overview of version changes.
 
 ## Compatibility
 
-- `v5` is the recommended version of [cypress-io/github-action](https://github.com/cypress-io/github-action)
+- `v6` is provided for early adopters needing full `node20` support
+- `v5` is the current recommended version
 - `v4` is the minimum version required for Cypress `10.x` and later
 
 Pay attention to any GitHub Actions deprecation warnings shown in logs which may recommend updating.