Created by: malesh
Generated csharp-netcore client fails to compile for a multi-file spec (see issue #10802 (closed)); fixed by updating template to handle an array of files.
Also added a sample that reproduces the issue; this was done in the first commit so reviewing commit-by-commit will show the effect the fix had on the generated client.
Closes #10802 (closed)
CC: @mandrean, @frankyjuang, @shibayan, @Blackclaws, @lucamazzanti