[BUG] Social links in footer not working

[AmnestyAM]

Describe the bug
When you add a Facebook or Twitter URL in the Theme options the logo is not visible in the front end.
Related - The field in the CMS validates for a full URL, but the URL is output twice for example href="https://twitter.com/https://twitter.com/duffuscf in the front end.

To Reproduce
Steps to reproduce the behaviour:

1. Go to /wp-admin/admin.php?page=theme-settings
2. Add a facebook and/or Twitter URL in the CMS
3. Go to /
4. See error in the footer

Expected behaviour
I expect the relevant logo to show and the link to go to the right URL

Screenshots
If applicable, add screenshots to help explain your problem.

Developer console output (if applicable):
N/A
Platform (please complete the following information):
whatsmybrowser.org/b/QBCHH6S

Additional context
N/A