Add CI test to run core, sync and object store tests against real iOS hardware

[sync-by-unito]

The current iOS tests only run against "simulated" iOS hardware on Jenkins CI, which is still using MacOS at the lowest level.

Add a set if tests that runs as part of the Evergreen nightly periodic build and performs the following tests against "real" iOS hardware using the AWS device farm:

• Core tests
• Sync tests
• Object store tests without baas
• Object store tests with baas, without TLS
• Object store tests with baas, with TLS (will need to create a specialized server cert and include it in the iOS app build)