add wasm mime override

Author: bollwyvl

jupyter_server/serverapp.py

@@ -1519,6 +1519,8 @@ def init_mime_overrides(self):
         # ensure css, js are correct, which are required for pages to function
         mimetypes.add_type('text/css', '.css')
         mimetypes.add_type('application/javascript', '.js')
+        # for python <3.8
+        mimetypes.add_type('application/wasm', '.wasm')
 
     def shutdown_no_activity(self):
         """Shutdown server on timeout when there are no kernels or terminals."""