Update build.yml to install the .NET SDK before launching .NET Arcade

.github/workflows/build.yml

@@ -28,6 +28,14 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v3
 
+    - name: Setup .NET
+      uses: actions/setup-dotnet@v3
+      with:
+        dotnet-version: |
+          3.1.425
+          6.0.403
+          7.0.100
+
     - name: Setup NuGet
       uses: nuget/setup-nuget@v1
       with:

global.json

@@ -4,15 +4,7 @@
   },
 
   "tools": {
-    "dotnet": "7.0.100",
+    "dotnet": "7.0.100"
-
-    "runtimes": {
-      "aspnetcore": [
-        "2.1.30",
-        "3.1.31",
-        "6.0.11"
-      ]
-    }
   },
 
   "msbuild-sdks": {