[iOS] Rename the build configurations back to the defaults
[iOS] Rename the build configurations back to the defaults

React Native currently heavily depends on the standard configurations
Debug and Release that XCode provides. Eg., the developer menu is
available only for the Debug configuration.

However, we have retained the values development, staging and production
for the user defined setting BUILD_ENV for now.

multunus/moveit-mobile,multunus/moveit-mobile,multunus/moveit-mobile