Update build.yml

Author: PartTimeLegend

.github/workflows/build.yml

@@ -21,7 +21,7 @@ jobs:
     - name: Setup .NET
       uses: actions/setup-dotnet@v4
       with:
-        dotnet-version: 9.0.203
+        dotnet-version: 9.0.300
 
     - name: Restore dependencies
       run: dotnet restore