Welcome to the site! Interestingly, we were talking about Tom Vuong on another thread, and here is one of his cotoneaster bonsai to motivate you! (It is a less common variety with orange berries instead of the more common red berries).
Cotoneaster are pretty hardy plants - even in Bakersfield - as long as you are gentle with their roots and don't mess with the roots (repotting, etc) during the heat of the summer. They can easily handle full sun, but need free-draining soil and do not like to sit in water / saturated dirt. Cotoneaster, from the Latin, means "resembling quince" and it grows similarly (in my opinion).
If you compare the foliage on your tree to the foliage on Tom's, you will note that your tree looks somewhat parched. This can be a function of not enough water OR a functional of
too much water, where the roots get choked from not having any oxygen and start to die. I don't know how your tree is being cared for, but sometimes you might see this in a tree that is sitting out in the heat of the day and you forget to water for several days.
Regardless, it appears to need some TLC. Gently slip it out of that black plastic nursery pot and check the health of the roots and soil and let us know what you find. In the interim, I would move this tree into shade cloth protection or indirect sun. Bakersfield still has some baking to do this year, and this little guy needs some love.