[release/10.0] Add backport.yml and flow configuration#2690

ViktorHofer merged 2 commits intorelease/10.0dotnet/command-line-api:release/10.0from

backport/pr-2689-to-release/10.0dotnet/command-line-api:backport/pr-2689-to-release/10.0Copy head branch name to clipboard