Updated build.xml and release.xml to .net8 version

Author: Srude-Vena

.github/workflows/build.yml

@@ -21,6 +21,7 @@ jobs:
       uses: actions/setup-dotnet@v3
       with:
         dotnet-version: |
+            8.0.x
             6.0.x
             3.1.x
 

.github/workflows/release.yml

@@ -22,7 +22,9 @@ jobs:
     - name: Setup dotnet
       uses: actions/setup-dotnet@v3
       with:
-        dotnet-version: '6.0.x'
+        dotnet-version: |
+            8.0.x
+            6.0.x
 
       # Finds the latest release and increases the version
     - name: Get next version