What can I do if I set myself on fire to stop being fire?

Multiple posts seem to claim that pressing the dodge button will help extinguish the fire:

GameFAQS:

keep tapping the dodge/evade button if not near water.

A Steam Post:

Hit space bar or your dodge button to dodge, it douses the flame faster

Another Steam Post:

You just have to mash the dodge button a few times. The game only really explains this via a tip on the loading screens.

And unsurprisingly, jumping into water will do the job as well, but you will obviously need to be near a body of water.