Comment 123 for bug 1518457

From man 7 udev:

The udev rules are read from the files located in the system rules directory /lib/udev/rules.d, the volatile runtime directory /run/udev/rules.d and the local administration directory /etc/udev/rules.d. All rules files are collectively sorted and processed in lexical order, regardless of the directories in which they live. However, files with identical filenames replace each other. Files in /etc have the highest priority, files in /run take precedence over files with the same name in /lib. This can be used to override a system-supplied rules file with a local file if needed; a symlink in /etc with the same name as a rules file in /lib, pointing to /dev/null, disables the rules file entirely. Rule files must have the extension .rules; other extensions are ignored.

As such, the best way to work around this is:

sudo ln -s /dev/null /etc/udev/rules.d/40-vm-hotadd.rules

Unlike deleting or modifying the original file, this will persist across upgrades without requiring manual conflict resolution.