Use pytest-xdist and 2 workers on CI when running the test suite

.github/workflows/tests.yml

@@ -45,7 +45,7 @@ jobs:
 
       - name: Run test suite
         run: |
-          pytest --pyargs exspy
+          pytest --pyargs exspy -n 2
 
       - name: Upload coverage to Codecov
         if: ${{ always() }}

pyproject.toml

@@ -2,4 +2,8 @@
 force-exclude = '''
   exspy/misc/eds/ffast_mac.py
   | exspy/misc/elements.py
-'''
+'''
+
+[tool.pytest.ini_options]
+addopts = "-ra -n auto --dist loadfile"
+testpaths = ["hyperspy/tests", ]

setup.py

@@ -45,6 +45,7 @@
         "pytest     >= 5.0",
         "pytest-mpl",
         "pytest-cov >= 2.8.1",
+        "pytest-xdist",
     ],
     "dev": ["black", "pre-commit >=1.16"],
 }