Updates .NET to version 8.x

Bumps the target .NET version in the build workflow from 6.x to 8.x, aligning with current development on the vNext branch.

Author: neoscie

.github/workflows/dotnet.yml

@@ -9,7 +9,7 @@ on:
 
 env:
   BUILD_CONFIGURATION: "Release"
-  DOTNET_VERSION: "6.x"
+  DOTNET_VERSION: "8.x"
 
 jobs:
   build: