[cache] Fix CAPCHA tokens not being replaced properly
This fixes CAPCHAs always failing when the page is cached. It slipped through this test:
- Go to a non-cached page.
- Post a comment to test non-cached commenting.
- Post another now that the page is cached.
I assumed that when posting a comment it redirected you back. Instead it redirects you to a URL without the language tag. This made my test work like this:
- Go to a non-cached page.
- Post a comment to test non-cached commenting.
- Post another on the non-cached different URL page.
No cached code was tested.