[Fleet] Synthetic source toggle does not appear for data streams without advanced settings + toggling behavior is broken

When a data stream does not include any advanced settings, the synthetic source toggle does not appear. 

Also, when toggling the synthetic source switch to `enabled`, other data streams have their switches toggled to `disabled` erroneously. See screen recording below.

https://user-images.githubusercontent.com/6766512/195126248-ba88f2da-c7be-4e3e-bf4d-b0b8d9839076.mov
