Kiali - Test to measure graph loading time

A cypress test to visit the graph page and wait for the graph to fully load.

This is separate from the other cypress testing efforts and more relates to scalability. As such, it does not need a feature file and can be written in the standard cypress syntax.

It will primarily be used for establishing a baseline of performance given different environments (large number of namespaces, workloads, time the workload has been deployed).

Github Issue:
https://github.com/kiali/kiali/issues/5143