CI: Skip network tests on macOS

Author: cyanfish

.github/workflows/dotnet.yml

@@ -24,4 +24,8 @@ jobs:
     - name: Build
       run: dotnet run --project NAPS2.Tools -- build debug -v
     - name: Test
+      if: matrix.os != 'macos-15'
       run: dotnet run --project NAPS2.Tools -- test -v --nogui
+    - name: Test (mac)
+      if: matrix.os == 'macos-15'
+      run: dotnet run --project NAPS2.Tools -- test -v --nogui --nonetwork