Okay this is the problem, when updating the application, JavaScript dependencies are retrieved using yarn, which means that the yarn.lock file is updated if dependencies are not correctly locked, which is the case here: this is a problem to fix.
Basically, you have to stash inside hrms before updating until the problem is fixed.
I opened a ticket for you here: yarn.lock outdated on branch version-15? · Issue #1947 · frappe/hrms · GitHub