Test failures on Gentoo Linux arm64

We are seeing several tests fail on Gentoo/arm64 with a message that doesn't give much information.

For example:

FAIL: test-pass
===============

Testing local backend with username-password... 
Connecting to obtain cookie... 
SSL connection failure: Error in the pull function.
Failed to open HTTPS connection to 127.0.0.2
Failed to complete authentication
Failure: Could not receive cookie from server
FAIL test-pass (exit status: 1)

The full test log is available on the Gentoo bug report.

Any tips on what might be causing this, or how we can further diagnose the issue?