refactor: ues language-specific command to load Python env

Author: JuroOravec

.github/workflows/tests.yml

@@ -43,16 +43,16 @@ jobs:
       run: |
         # NOTE: maturin requires a virtual environment to be active
         python -m venv .venv
-        source .venv/bin/activate
+        ${{ runner.os == 'Windows' && '.venv\Scripts\activate' || 'source .venv/bin/activate' }}
         python -m pip install --upgrade pip
         python -m pip install -r requirements-ci.txt
 
     - name: Build Python package
       run: |
-        source .venv/bin/activate
+        ${{ runner.os == 'Windows' && '.venv\Scripts\activate' || 'source .venv/bin/activate' }}
         maturin develop
 
     - name: Run Python tests
       run: |
-        source .venv/bin/activate
+        ${{ runner.os == 'Windows' && '.venv\Scripts\activate' || 'source .venv/bin/activate' }}
         pytest