Sanitise project path on windows for doc build

Author: OliverDavey

tests/scrape_images.py

@@ -13,7 +13,8 @@ class MachineScraper:
 
     def __init__(self, project_root):
         self.project_root = project_root
-        self.re_machine_module_name = re.compile(f"{self.project_root}/(.*).py$")
+        sanitized_path = self.project_root.replace("\\", "\\\\")
+        self.re_machine_module_name = re.compile(f"{sanitized_path}/(.*).py$")
         self.seen = set()
 
     def __repr__(self):