Nightingale fixes for Aspiring Chief Exec VC

[ishanivardhan]

In order to deliver Aspiring Chief Exec with Nightingale, following fixes are needed:

• [ ] Course description text overlap with Course title on Home page
• [ ] Line spacing on Course Index page not consistent
• [ ] Paragraph spacing not consistent
• [ ] Need dividers between topics (Refer Boost theme)
• [ ] Prev/Next buttons missing from course content pages

[penpadstudio]

@ishanivardhan @adamref @cehwitham Line spacing, margins and paragraphs can all be referenced from the Nightingale repo. There is also a wiki that documents what they should be: https://github.com/NHSLeadership/nightingale Also have visual representations that can be accessed via abstract: https://share.goabstract.com/a0def21d-951d-4b6e-af56-7a0d21fe6de7