Hopefully this will fix the CI tests. This is a common enough issue on CI that Travis mentions it in their documentation: https://docs.travis-ci.com/user/common-build-problems/#linux-apt-fails-to-install-package-with-404-error
Hopefully this will fix the CI tests. This is a common enough issue on CI that Travis mentions it in their documentation: https://docs.travis-ci.com/user/common-build-problems/#linux-apt-fails-to-install-package-with-404-error