Remove hash navigation fix
Remove hash navigation fix

This isn't used anywhere. It also has logic in it to ensure the sticky
heading bar doesn't cover the content. The header bar isn't sticky and
hasn't been for ages.

alphagov/static,kalleth/static,alphagov/static,tadast/static,kalleth/static,robinwhittleton/static,tadast/static,tadast/static,robinwhittleton/static,kalleth/static,robinwhittleton/static,kalleth/static,tadast/static,robinwhittleton/static,alphagov/static