Add example for join point where multiple features from a join point configuration contend, and the first one(s) do not apply

[TomStrepsil]

A common setup at ASOS was to target the same join point module for an experiment.

For the sanctity of analysis, experiments that target the same components are ideally designed with exclusion groups, or to not overlap during their run.

However, where exclusion groups cannot apply because the toggle router (e.g. the Edge-based router at ASOS) has insufficient audience data to split the cohorts, and there is a need to overlap the run of A/B tests, it's desirable to attempt a bucketing decision at run time for all the potential groups per join point, and then partition the data later in analysis instead.

The react-pointcuts toggle points do cater for this scenario, but there is no example in the codebase to demonstrate (and to provide a test fixture for regression avoidance).