It's unlikely, it seems they are just migrating for food.
As Al Nash, chief of public affairs for Yellowstone, explained in a rumor control video on this subject:
We do have bison, elk and other animals that have moved outside the
park recently, but they're doing that because it's the depth of
winter, food is a little hard to find in places inside Yellowstone,
and they tend to migrate at this time of the winter outside the park
to lower elevations where they think there might be something to eat
that's easier to get at. When the snow melts off and things start to
green up, those very same animals will walk right back into the park.
Additionally, the video displayed above was actually taken more than two weeks before the 30 March 2014 earthquake that triggered fears of an upcoming eruption at Yellowstone and shows bison running into the park, not away from it:
Leo Leckie, a sales associate of the nonprofit Yellowstone Assn. ...
shot the video, which lasts 1 minute and 9 seconds and was originally
posted March 14 on his Facebook page under the title, "Yellowstone
bison on the run for the joy of Spring."
"Those bison were running for the sake of running," Leckie said in an
interview. "There was nothing chasing them. There was no mudslide.
They were just running."
Added Leckie: "And they were running into the park, not away from it."