Please tell me this is not a serious question....kind of off topic, other than it's kinda creepy.

Apologies to
@XanderWiFi for extending the topic diversion.
It
is submissive. Active layers will often submit like that when the human keeper walks near, especially if there is no cock/erel present, but please don't mount them.
Some folks will give them a back pat or scratch, then the bird will stand up and shake her tail feathers to distribute the semen as she walks away-despite the fact that (hopefully) none was deposited, but I seriously doubt it is necessary to respond to a squatting chicken. I've always had a male in my flock so rarely have a pullet/hen squat near me.
A bird may also submit like that if it feels it is going to be attacked/bullied/pecked.