dotnet.yml: Do dotnet pack and upload-artifact.

Based on https://github.com/ektrah/nsec/blob/master/.github/workflows/test.yml. This allows the creation of a package without having iOS, TvOS, and Mac Catalyst set up on my machine.

.github/workflows/dotnet.yml

@@ -1,4 +1,4 @@
-name: Build and Test
+name: Build, test, and pack
 
 on: [push, pull_request]
 
@@ -21,6 +21,8 @@ jobs:
         dotnet-version: |
           6.0.x
           8.0.x
+    - name: Install workloads
+      run: dotnet workload install ios tvos maccatalyst
     - run: dotnet --info
     - name: Test (.NET 8.0/Debug)
       run: dotnet test -f net8.0 -c Debug
@@ -30,8 +32,15 @@ jobs:
       run: dotnet test -f net6.0 -c Debug
     - name: Test (.NET 6.0/Release)
       run: dotnet test -f net6.0 -c Release
+    - name: Pack
+      run: dotnet pack -c Release
+    - name: Upload artifacts
+      uses: actions/upload-artifact@v4
+      with:
+        path: '**/*.nupkg'
 
   test-linux-x64:
+    needs: test-windows-x64
     runs-on: ubuntu-latest
     env:
       DOTNET_CLI_TELEMETRY_OPTOUT: 1
@@ -55,6 +64,7 @@ jobs:
       run: dotnet test -f net6.0 -c Release
 
   test-macos-x64:
+    needs: test-linux-x64
     runs-on: macos-latest
     env:
       DOTNET_CLI_TELEMETRY_OPTOUT: 1
@@ -78,6 +88,7 @@ jobs:
       run: dotnet test -f net6.0 -c Release
 
   test-linux-musl-x64:
+    needs: test-macos-x64
     runs-on: ubuntu-latest
     container:
       image: mcr.microsoft.com/dotnet/sdk:8.0-alpine