Upgrade Chart.JS dependency

Why?

The current version of Chart.JS used in Queue (2.x.x) which was first used in 2016. Since then 2 new major versions have been released with them stating the following:

In order to improve performance, offer new features, and improve maintainability, it was necessary to break backwards compatibility, but we aimed to do so only when worth the benefit.

The reason we need to upgrade is that some of the charts defined in the wireframe (stacked bar charts with vertical stacks (not groups alongside eachother)) only became readily available in a later version. In addition to this the I like the newer syntax.

What needs to be done

• Chart.JS dependency version needs to be updated in the gradle build file
• Existing charts need to be changed to use the newer syntax, and functionality has to be tested

Migration

Migration guides are provided in the docs for 3.x.x and 4.x.x