Okay I'll bite...but only cos it is one of my favourite films and I was seriously thinking of it as a middle name.
Juno is indeed the teenager who gets pregnant but is sassy, intelligent and funny.
Her father (the wonderful JK Simmons) installs heating systems or some such so blue collar work who happens to like roman mythology
Her stepmum does nails and to the snarky 'ultrasound technician' basically says Yes and I'm a nail technician, doesn't mean you can judge my dumbass stepdaughter or words to that effect
As the lead character describes it, the goddess Juno was supposed to be 'very beautiful but really mean, like Diana Ross'

I have never taught a Juno.
I would assume parents choosing that name had
a) excellent taste in film
b) an interest in mythology or
c) a June baby but thought June was old-fashioned
If I didn't know and love the movie I might previously have thought hmm pretentious, much but would think that of any mythological names (if I had judgy pants on!)
hth