Add no-cache headers to static files. (#526)

Author: Dreamsorcerer

aiohttp_devtools/runserver/serve.py

@@ -363,4 +363,8 @@ async def _handle(self, request: web.Request) -> web.StreamResponse:
         else:
             # Inject CORS headers to allow webfonts to load correctly
             response.headers['Access-Control-Allow-Origin'] = '*'
+
+        # Add no-cache header to avoid browser caching in local development.
+        response.headers["Cache-Control"] = "no-cache"
+
         return response