Fix pip upgrade issue (#559)

* Fix pip upgrade issue

* Fix pip upgrade issue

Author: ahartikainen

.github/workflows/main.yml

@@ -53,7 +53,7 @@ jobs:
 
       - name: Install dependencies (python)
         run: |
-          pip install --upgrade pip wheel
+          python -m pip install --upgrade pip wheel
           pip install -r requirements.txt
           pip install -r requirements-test.txt
           pip install codecov

.github/workflows/release.yml

@@ -32,7 +32,7 @@ jobs:
 
       - name: Install dependencies (python)
         run: |
-          pip install --upgrade pip wheel twine codecov sphinx nbsphinx ipython ipykernel pydata-sphinx-theme requests sphinx-copybutton matplotlib
+          python -m pip install --upgrade pip wheel twine codecov sphinx nbsphinx ipython ipykernel pydata-sphinx-theme requests sphinx-copybutton matplotlib
           pip install -r requirements.txt
           pip install -e .