Dynamic Type font support on Apple Devices

[davidhunter08]

We need to review adding support for Dynamic Type on Apple devices.

NHS.UK frontend team made some changes:

• PR #1655 for guidance:
• Make sure form controls scale with text size
• Make sure other components scale with text size
• Use scalable details expander icons (where supported)

Advice from @colinrotherham:

Try not to scale everything, just things that are tied to the text size.

Otherwise from a web point of view you’ll start turning a desktop layout back into a mobile one.