From Chromely version v5 up we support Raspberry Pi's linux-arm as target platform.
To publish for this platform use the following command.
dotnet publish -c Release -f netcoreapp3.1 -r linux-arm -p:PublishSingleFile=true -p:PublishTrimmed=true
Call it from the directory where the project is.
It will create a single file executable for Raspberry Pi use.
Warning!
The download and unpack process on the PI is slow and may take several minutes - be patient.