[REF] Code cleanup on membership renewal & test

[REF] Code cleanup on membership renewal & test

This wound up being mainly a clean up of the test class & the addition of a test on changing
membership type.

However, there is a minor code consolidation which makes 3 actual changes
1) if we are doing a test renewal we shouldn't make the membership test
2) even when renewing a Pending membership we should save any submitted custom data
3) modified id is also set for pending (although future test work might indicate this can go