this is a feature of your smartphone, depending on the model there are different settings that let you control how your pictures are uploaded.
For example, with the camera app open on an Android device, when in Photo mode the options are displayed across the top banner, you want to turn off “motion photo”
This article describes turning the feature on. you can just do the opposite to turn it off.
for Iphone, this article describes enabling motion photos,
again do the opposite to turn it off