Fix CI: Explicitly restore before running tests

Restore test project first (which restores main project as dependency),
then run tests with --no-restore to use the restored dependencies.
This ensures xunit is in the assets file before building.

Author: Alex J Lennon

.github/workflows/ci.yml

@@ -29,11 +29,11 @@ jobs:
     - name: Clean build artifacts
       run: rm -rf obj bin
 
+    - name: Restore dependencies
+      run: dotnet restore tests/InstDotNet.Tests.csproj
+      
     - name: Run Tests
-      run: |
-        # Just run tests - dotnet test will build both projects as needed
-        # The test project depends on the main project, so both get built correctly
-        dotnet test tests/InstDotNet.Tests.csproj -c Release -p:GitCommitHash=${{ steps.git.outputs.hash }} --verbosity normal
+      run: dotnet test tests/InstDotNet.Tests.csproj -c Release -p:GitCommitHash=${{ steps.git.outputs.hash }} --no-restore --verbosity normal
       continue-on-error: false
 
   build: