fix: terminal link highlighter inside box

[mxschmitt]

Sometimes we print commands inside a box:

    ╔═════════════════════════════════════════════════════════════════════════╗
    ║ Looks like Playwright Test or Playwright was just installed or updated. ║
    ║ Please run the following command to download new browser:               ║
    ║                                                                         ║
    ║     npx playwright install chromium-headless-shell                      ║
    ║                                                                         ║
    ║ <3 Playwright Team                                                      ║
    ╚═════════════════════════════════════════════════════════════════════════╝

this was then not working correctly with the link highlighter which included the right box character. The new regex won't do that anymore.