Trying a baseline build, but incompatible with python 3.10

I have downloaded the source code (V1.12.3) and I am trying to build from it. I have found a few minor tweaks that needed to be made, that I can keep in my own repository, but one is buried in a submodule that I don’t seem to be able to maintain. The make complains about:
src/drivers/uavcan/px4_uavcan_dsdlc_run.stamp /home/hskrieg/fw/PX4-Autopilot/build/cubepilot_cubeorange_default/src/drivers/uavcan/px4_uavcan_dsdlc_run.stamp
libuavcan_dsdlc_run.stamp /home/hskrieg/fw/PX4-Autopilot/build/cubepilot_cubeorange_default/libuavcan_dsdlc_run.stamp
AttributeError: module ‘collections’ has no attribute ‘MutableSequence’

It seems that the change from python 3.9 to 3.10 removed this attribute, but changing to will keep it working. The lines to be changed are:
ln 10: import collections to import
ln 202: collections.MutableSequence to

At this time, I don’t know how to commit this to my own repository, and it seems like it would be a good idea to fix this in the main repository.