Microsoft Visual Studio 2019 ships with LLVM/Clang 12 as of Visual
Studio 2019 16.11.0 (August 10, 2021). LLVM/Clang 12 is available on all
platforms. This change should make it easier to have clang-format "just
work" on dev systems and be consistent across platforms without having
to use an outdated version.
There are too many issues with 20.04 to successfully build with
VirtualCam - the azure kernel is missing videodev headers. For now,
use 18.04 LTS directly for main CI builds.
Both 18.04 and 20.04 include clang-format-10 without issue.
