Building custom image fails - cannot find "dtbs" in kernel info

EDIT: For anyone encountering this, can be solved with Changes in pi/pi-kernel DTB handling

I’m having the same issue on my device rpi with core18 based on pi-gadget, albeit when installing it on an existing device.

I can’t update the pi-kernel due to

Update assets from kernel "pi-kernel" (357)
2021-10-28T16:55:59+02:00 ERROR gadget does not consume any of the kernel assets needing synced update "dtbs"

And I can’t update the gadget due to

error: cannot perform the following tasks:
- Update assets from gadget "my-gadget" (unset) (cannot resolve content for structure #0 at index 0: cannot find "dtbs" in kernel info from "/snap/pi-kernel/326")

$ ls /snap/pi-kernel/current/dtbs/
bcm2708-rpi-b-plus.dtb  bcm2708-rpi-zero-w.dtb  bcm2710-rpi-2-b.dtb       bcm2710-rpi-cm3.dtb   ...