CI - lots of things wrong, try that again

.github/workflows/ci.yml

@@ -8,23 +8,31 @@ on:
   workflow_dispatch: # manual trigger
 
 jobs:
-  build_test:
-    strategy:
-      matrix:
-        os: [ubuntu-latest, windows-latest]
-        framework: [net6.0, net481, net461]
-    runs-on: ${{ matrix.os }}
+  build-test-ubuntu:
+    runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v4
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v4
         with:
-          dotnet-version: |
-            6.0.x
-            4.8.1
-            4.6.1
+          dotnet-version: 6.0.x
+
+      - name: Restore dependencies
+        run: dotnet restore
+
+      - name: Test
+        run: dotnet test --framework net6.0 -c Release /p:CollectCoverage=true /p:Threshold=80 /p:Include=\"[Flurl]*,[Flurl.Http]*,[Flurl.Http.Newtonsoft]*\" /p:Exclude="[*]*.GeneratedExtensions"
+
+  build-test-windows:
+    runs-on: windows-latest
+    strategy:
+      matrix:
+        framework: [net481, net461]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
 
       - name: Restore dependencies
         run: dotnet restore