Articles 348.60 and 350.60 both require an EGC where flexibility is necessary, but it does not say anything about that EGC excepting any requirement for electrical continuity of the raceway itself.
In the same sections, and under certain [limited] conditions, FMC can itself satisfy a continuity requirement.
And all of these wiring method grounding and bonding requirements state:
I realize it's a common installation (without a bonding jumper). Not saying it has to be one way or another to be compliant, but doing it when you don't know its non-compliant is one thing. Doing it when you do know it's non-compliant is another. Perhaps we should all just be oblivious to the requirements we don't like (sarcasm).