BUG Sort out the colour updates for the measurement station lines

[rstrange-scottlogic]

We have some code that is responsible for updating the colours of the lines in the measurement charts. In the SingleCity.tsx page we have a bunch of code setting site colorus, which calls updateColors() etc.

When running locally this code appears to work fine, and you can see the colours changing on the loaded graphs (easier to see with more stations, i.e. Tokyo). The lines are made darker and more prominent as well as changing colour.

On the deployed version we do not see this, and the default eCharts colours are still shown. We also receive a JS error in the browser console, which may be related.

We should do either

1. fix the error so the colour change also happens on the deployed version,
2. delete the code and leave the eCharts colours as they are on our deployed version too.

We will fix!

Hopefully whichever we choose will sort out the error occurring on the browser (seen in Chrome at least)

Example of the issue :

Ideas to test:

• check prod issue in screenshot is resolved
• automation for one city site - cryptographically hash station name, small graph with one station, assert colour or if not possible, screenshot test would work

[lincent]

Charter here -> https://github.com/ECMWFCode4Earth/vAirify/wiki/Charter-25:-Line-Colours