Added link checker to github actions

[Mil4n0r]

Checklist (Check off all the items before submitting)

• [ ] Build process is done without errors. All tests pass in the /lib directory.
• [ ] Self-reviewed the code before submitting.
• [ ] Meets accessibility standards.
• [ ] Added/updated documentation to /website as needed.
• [ ] Added/updated tests as needed.

Description lychee-action has been setup in our project to look for broken links. In case that there is any, it will automatically open a Issue regarding indicating what link is broken and where it is located.

Screenshots

Closes #1972

[Mil4n0r]

Work in progress. The following changes are pending:

• Removing the automatic creation of issues when detecting broken links.
• Checking only lib/ and website/ (app/ is not needed as it is used for testing purposes).

[Mil4n0r]

Applied the suggested changes. Ready to review now.