Update apexcharts.js to the latest stable version

[EusebiuOprinoiu]

This commit updates the apexcharts.js library to the latest stable version.
It resolves conflicts with other plugins that use the same library, as described in this thread on the WordPress Forum.

The jump from version 3.x to version 5.x comes with very minor CSS changes, the most notable one being that Markers are now squares (instead of circles) and that the labels have a larger font size.

The CSS tweaks in the admin.css file address these changes to ensure the widget design remains unchanged.

[EusebiuOprinoiu]

I'm not sure how external libraries should be handled when multiple plugins bundle them, so I leave that up to you if you want minimize conflicts. Ideally, a library should only be loaded once.
At least with the latest version, the widget from the admin dashboard no longer breaks.

I also notice that with the old version, the highest peak of a chart used to reach the top of the graph.
With the new version, the highest peak is lower. (at least for the Times, Bytes, and Calls tabs - for the Ratio tab, it still reaches the top)
I presume some minor changes need to be made in the admin.js file as well, but I'm not very good with JavaScript, so I leave that up to you.

[tillkruss]

Redis Object Cache loads the charts on these screens: roc-settings, dashboard, dashboard-network. Can you confirm where your other plugin loads the charts?

[EusebiuOprinoiu]

The other plugin loads the charts only on the main dashboard. ( dashboard )
If you need to test, you can install this plugin:
https://wordpress.org/plugins/merchant