Add DigitalOcean to thanks section of README (#7547)

* Add DigitalOcean to thanks section of README

Fixes #7546

Add DigitalOcean to the thanks section of the README.

* Add a note in the `README.md` file to thank DigitalOcean for generously providing Node.js with credits as part of their open source program.
* Add a note in the `apps/site/README.md` file to thank DigitalOcean for generously providing Node.js with credits as part of their open source program.

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For more details, open the [Copilot Workspace session](https://copilot-workspace.githubnext.com/nodejs/nodejs.org/issues/7546?shareId=XXXX-XXXX-XXXX-XXXX).

Author: ovflowd

README.md

@@ -114,6 +114,7 @@ These are maintained in different repositories and we urge users to open **issue
 - Thanks to [Sentry](https://sentry.io/welcome/) for providing an open source license for their error reporting, monitoring and diagnostic tools.
 - Thanks to [Crowdin](https://crowdin.com/) for providing a platform that allows us to localize the Node.js Website and collaborate with translators.
 - Thanks to [Orama](https://docs.oramasearch.com/) for providing a search platform that indexes our expansive content and provides lightning-fast results for our users.
+- Thanks to [DigitalOcean](https://www.digitalocean.com/) for generously providing Node.js with credits as part of their open source program.
 
 [code of conduct]: https://github.com/nodejs/admin/blob/main/CODE_OF_CONDUCT.md
 [contribution guidelines]: https://github.com/nodejs/nodejs.org/blob/main/CONTRIBUTING.md