The problem has been fixed. Here is the email from support at Avast.
Hello,
Thank you for contacting Avast and reporting false positive URL detection. I am glad to help.
Reported website was checked by Avast virus specialists and based on the findings the detection was turned off.
The website is now marked as clean in the Avast virus database. This change should be instant but it might take up to 24 hours in some cases. Please accept my apology for the inconvenience caused.
If the detection persists after the 24 hours, please update Avast virus database first and reply to this email with attached files:
1. Take a screenshot of the Avast detection dialog with "See details" in the bottom-right corner displayed.
2. Take a screenshot of the Avast virus database - go to Avast Antivirus to "Menu - About"
Have a nice day!
Best Regards,
Fran
The Avast Support Team