Cache policy with environment flag and identity flags conflicts

[bamanrich]

Let say I configure a FlagsmithCache of 1 minute.

If I call getEnvironmentFlags and then call getIdentityFlags, then the first cached call will be returned for the second call.

I feel like this behavior is error prone as we don't expect to have the "default" value of environment flags when we request for a specific identity override, even if we cache the results of the API.

[matthewelwell]

Thanks for raising this @bamanrich - I totally agree with you here. I'll look to roll this into a new release in the near future.