The /dev location is a special place in Linux
https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/dev.html
It normally does not contain regular files. Do an "ls -al" on that path and you will likely see a special attribute. Its probably a link to a file thats located in /var.
Keep in mind that shrinking raw, qemu or other image files when not done with appropriate preparations, will lead to data loss.
good luck
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