CI: test using .NET 5

resolves

Author: swharden

.github/workflows/ci.yaml

@@ -18,10 +18,10 @@ jobs:
     steps:
       - name: 🛒 Checkout
         uses: actions/checkout@v2
-      - name: ✨ Setup .NET 6
+      - name: ✨ Setup .NET 5 # CI: do not increase this
         uses: actions/setup-dotnet@v1
         with:
-          dotnet-version: "6.0.x"
+          dotnet-version: "5.0.x"
       - name: 🚚 Restore
         run: dotnet restore
       - name: 🛠️ Build

.github/workflows/publish.yaml

@@ -16,7 +16,11 @@ jobs:
     steps:
       - name: 🛒 Checkout
         uses: actions/checkout@v2
-      - name: ✨ Setup .NET 6
+      - name: ✨ Setup .NET 5 # CI: keep this for building and testing
+        uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: "5.0.x"
+      - name: ✨ Setup .NET 6 # CI: keep this for packing
         uses: actions/setup-dotnet@v1
         with:
           dotnet-version: "6.0.x"