github actions: added windows ci coverage (#4)

Co-authored-by: Markus Staab <[email protected]>

Author: staabm

.github/workflows/unit-tests.yml

@@ -14,6 +14,8 @@ jobs:
         strategy:
             matrix:
                 include:
+                    -   os: windows-latest
+                        php-version: '8.0'
                     -   os: ubuntu-latest
                         php-version: '8.0'
                     -   os: ubuntu-latest