style: activate string normalization

test/test_projects/base.py

@@ -8,12 +8,12 @@ TemplateContext = Dict[str, Any]
 
 
 class TestProject:
-    '''
+    """
     An object that represents a project that can be built by cibuildwheel.
     Can be manipulated in tests by changing `files` and `template_context`.
 
     Write out to the filesystem using `generate`.
-    '''
+    """
 
     __test__ = False  # Have pytest ignore this class on `from .test_projects import TestProject`
 
@@ -29,7 +29,7 @@ class TestProject:
             file_path = path / filename
             file_path.parent.mkdir(parents=True, exist_ok=True)
 
-            with file_path.open('w', encoding='utf8') as f:
+            with file_path.open("w", encoding="utf8") as f:
                 if isinstance(content, jinja2.Template):
                     content = content.render(self.template_context)