Forms cannot accept extra fields not in the form (affects pagination) #10

Describe the bug
We want to support optional extra fields that do not appear in the HTML form.

Example:

• Go to Help https://rnib-bookshare.ddev.site/help
• Enter search query: rnib
• Click on pagination for page 2
• This creates a pagination link: https://rnib-bookshare.ddev.site/help/search?search=rnib&page=2

The form needs to support the optional GET param "page" which we do not want to display in the form.

Expected behavior
Form can return optional fields passed, e.g. "page"