Update pkgdown website reference pages

[Olivia-Box-Power]

The charts on this page of the website need fixing

https://best-practice-and-impact.github.io/afcharts/reference/scale_fill_discrete_af.html

• use_afcharts is being applied even though it isn't in the examples. Update the example code for the use_afcharts to switch it off when finished.
• The bars on the sequential bar chart are not in order. This is due to the machine that built the website using a different alphabetical order than local machine. Make age a factor to fix this.
• Make charts wider so x axis labels aren't squished together.