Fix loading code from URI

Previously, if you hit the "Copy URL" button and visit the URL in a
different tab, you would not get the code that you had in the editor.
For example, try https://try.ruby-lang.org/playground/#code=no&engine=cruby-3.2.0dev

Additionally, if you edit the code in the URL and hit enter, you'd get a
error in the JS console.

Both of these issue were caused by getting a string back that start with
a '#'. Delete this prefix.

Author: XrXr

source/javascripts/try_ruby.js.rb

@@ -468,7 +468,7 @@ def do_change_lang(event)
 
   # Playground methods
   def get_state_from_url
-    hash = $document.location.fragment.to_s
+    hash = $document.location.fragment.to_s.delete_prefix('#')
     hash = Browser::FormData.parse_query(hash.gsub('+', ' '))
     [hash['code'], hash['engine']]
   end