Fixing issue #20436

The module did not initialize the variable uri

Author: Desiree05

modules/auxiliary/dos/http/apache_range_dos.rb

@@ -98,7 +98,7 @@ def check_for_dos
   end
 
   def conduct_dos
-    datastore['URI']
+    uri = datastore['URI']
     rhost = datastore['RHOST']
     ranges = ''