Update link to ankiweb page for author's add-ons

[BjoernLudwigPTB]

Description

There is a link in the support dialog supposed to open the ankiweb page, listing all your add-ons, which assumingly changed over time. This now is the corrected version.

Thanks for your great work!

Checklist:

Please replace the space inside the brackets with an x and fill out the ellipses if the following items apply:

• [x] I've read and understood the contribution guidelines
• [ ] I've tested my changes against at least one of the following Anki builds:
  • [ ] Latest standard Anki 2.1 binary build
  • [ ] Latest alternative Anki 2.1 binary build
• [x] I've tested my changes on at least one of the following platforms:
  • [x] Linux, version:
  • [ ] Windows, version:
  • [ ] macOS, version:
• [ ] My changes potentially affect non-desktop platforms, of which I've tested:
  • [ ] AnkiMobile, version:
  • [ ] AnkiDroid, version:
  • [ ] AnkiWeb