github CI: test x86 on Windows

32-bit MSVC is available and should be tested.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

.github/workflows/on_PR_windows_matrix.yml

@@ -76,7 +76,6 @@ jobs:
           cmake --install build
 
       - name: Test
-        if: ${{matrix.platform == 'x64'}}
         run: |
           ctest --test-dir build --output-on-failure