fix(gitArbor TUI link): removed the broken github link and replaced i…

[nivedhz]

…t with the website link.

PR Description

• Fixed the link from a broken github one to https://gitarbor.com/

Please check if the PR fulfills these requirements

• Cheatsheets are up-to-date (run go generate ./...)
• Code has been formatted (see here)
• Tests have been added/updated (see here for the integration test guide)
• Text is internationalised (see here)
• If a new UserConfig entry was added, make sure it can be hot-reloaded (see here)
• Docs have been updated if necessary
• You've read through your own file changes for silly mistakes etc