update CI

Author: leastprivilege

.github/workflows/ci.yml

@@ -21,10 +21,17 @@ jobs:
     steps:
     - uses: actions/checkout@af513c7a016048ae468971c52ed77d9562c7c819
 
-    - name: Setup dotnet (main)
+    - name: Setup net6
       uses: actions/setup-dotnet@v1
-      
-    - name: Setup dotnet (testing netcore3)
+      with:
+        dotnet-version: '6.0.x'
+
+    - name: Setup net5
+      uses: actions/setup-dotnet@v1
+      with:
+        dotnet-version: '5.0.x'
+
+    - name: Setup net3
       uses: actions/setup-dotnet@v1
       with:
         dotnet-version: '3.1.x'