XMLHttpRequest: remove meaningless import from server file

Author: annevk

xhr/resources/parse-headers.py

@@ -1,10 +1,6 @@
-import json
-
 def main(request, response):
-
     content = ""
     if "my-custom-header" in request.GET:
         val = request.GET.first("my-custom-header")
         response.headers.set("My-Custom-Header", val)
-
     return content