Updated CI to use .net 9

Author: imperugo

.github/workflows/dotnetcore.yml

@@ -36,24 +36,17 @@ jobs:
         with:
           dotnet-version: |
             2.1.x
-            6.0.x
-            7.0.x
             8.0.x
+            9.0.x
 
-      - name: Run .NET 8 Tests
-        run: dotnet test -f net8.0
-        shell: bash
-        env:
-          REDIS_HOST: localhost
-
-      - name: Run .NET 7 Tests
-        run: dotnet test -f net7.0 --verbosity quiet
+      - name: Run .NET 9 Tests
+        run: dotnet test -f net9.0
         shell: bash
         env:
           REDIS_HOST: localhost
 
-      - name: Run .NET 6 Tests
-        run: dotnet test -f net6.0 --verbosity quiet
+      - name: Run .NET 8 Tests
+        run: dotnet test -f net8.0
         shell: bash
         env:
           REDIS_HOST: localhost
@@ -71,9 +64,8 @@ jobs:
         with:
           dotnet-version: |
             2.1.x
-            6.0.x
-            7.0.x
             8.0.x
+            9.0.x
 
       - name: Build with dotnet
         run: ./NuGetPack.bat