[shinyReport("transmitters")] Add line thickness in connectivity plot

[fmaron]

Is your feature request related to a problem? Please describe.
At the moment, there is no increase in line thickness if the connections between stations are higher. There is a change in how bold the line is.

Describe the solution you'd like
Add line thickness to the connectivity plot.

Describe alternatives you've considered
No alternatives yet

Additional context
Charlie's comment:

Line thickness doesn't really seem to vary

[fjaine]

Should be possible to edit line width in ggraph. Check out this post in case it's helpful: https://stackoverflow.com/questions/56496168/legend-line-thickness-in-ggraph

Here, the line width would depend on the number of links/connections travelled between two stations.