This happened on both tvOS (x86_64) and macOS (x86)  when bumping to mono-4.8.0-branch 5aba8a05f147ab1d12414c8f072657531b1c97f1
However iOS (x86, x86_64) and watchOS (x86) did not fail.
The PR that did the same bump for master (previous was on d15-1) also had the same failure on mac (x86)
Since we have never seen it before it looks like something changed (regressed or cause it to happen far more frequently) since the previous bump.
https://jenkins.mono-project.com/job/xamarin-macios-pr-builder/3218/Test_Report/ (watchOS - simulator)
Should have been 'Infrastructure' but I disabled it :)
Not a big deal we can re-open it in maccore if it ever happens again