testing/dotnet6: enable armv7 / armhf
Description
armv7 / armhf support for dotnet6.
A parallel thread exists on Microsoft's side here:
Hurdles
- source-build does not support armv7 / armhf despite there being prebuilt binaries available
- Pipelines do not run on armv7 / armhf hardware, but rather within virtualized 32-bit cores on aarch64 hardware. This is detected as armv8l, causing issues with dotnet's arch detection logics
Edited by Antoine Martin