RSpec: Add test for X-Api-Key to diaper_bank_client_spec.rb

[NiquiCara]

This issue is work remaining from #51.

Services

diaper_bank_client_spec.rb

These need additional tests, but it will be hard to test them without the guard clause stopping non-Prod

• post_request sets the X-Api-Key

[samudary]

I can handle this as well

[edwinthinks]

@samudary hey there -- just checking in are you actively working on this issue still?

[samudary]

@edwinthinks Hi, I'll be completing this issue and starting the next one assigned to me later this week.