1706 reflow instances of two dimensional scroll

[GCHQ-Developer-299]

Summary of the changes

The following pages have had reflow issues fixed: Get Started > Testing with Jest and React Testing Library (the Code Preview component variant used here might be the issue, it doesn't wrap nicely like the Components pages one does)

• Get Started > Testing with Cypress
• Get Started > Migrating to V3
• Accessibility > Auditory Needs, Motor Needs, Visual Needs
• Accessibility > Invisible Illness, Neurodiversity
• Accessibility > Subtitling, Transcripts and Audio Description
• Styles > Colour
• Styles > Icon Groups Big change here, replaced the Icon Group display component
• Styles > Layout and Spacing
• Components > Types
• Patterns > Top/Side Navigation Layout
• Patterns > App Errors
• Patterns > Form Validation Note: The ic-text-fields still spill off the page, i've raised #4071 for fixing them
• Patterns > Success Messages
• Community > Glossary of Terms

Related issue

#1706

Checklist

• [x] I have manually accessibility tested any changes, if relevant.
• [x] I have raised this pull request against the develop branch

[github-actions[bot]]

View your branch deployment here: https://mi6.github.io/ic-design-system-githubpages/branches/1706-reflow-instances-of-two-dimensional-scroll

[lz405]

On the 'Testing with Cypress' and 'Testing with Jest' pages I'm still getting reflow issues when between a width of exactly 768px and roughly 1000px (depending on width of content).

~775px width

[GCHQ-Developer-299]

On the 'Testing with Cypress' and 'Testing with Jest' pages I'm still getting reflow issues when between a width of exactly 768px and roughly 1000px (depending on width of content).

~775px width

I think i've addressed this now :)