D10 readiness

[gareth-weston]

WILSON-0: Updates core version to use D9/D10 WILSON-0: Updates base theme for D9/D10 WILSON-0: Imports file url service and updates logic WILSON-0: updates twig logic to resolve twig syntax error.

[AccessPaul]

Thanks a million for the initial work on this @gareth-weston! 🌟

I've extended this by:-

• following up on the feedback from Sophie
• updating some contrib dependencies to D10 compatible versions
• removing deprecated RDF core module from install
• removed references to Stable core theme as there's actually no reason for the Wilson theme to use it as a base
• removed some deprecated references to #drupal-off-canvas in the admin CSS module
• added a fix for section background overlay pseudo element not resizing correctly (this was recently fixes in SCJP so using the same fix of the translate3d hack)

I've tested this branch upgrading from D9.5 and also done a clean install straight in to D10 and this works nicely so I'm going to merge and tag from this.