[QGIS-Developer] Removing MXE windows cross builds from QGIS repo

[Alessandro Pasotti]

Hi all,

Unless anybody objects I'm going to remove MXE cross builds from
GitHub workflows and all the relative code in ms-windows/mxe folder.

I still think it is a useful feature for quick testing on windows but
it breaks from times to times (see the protobuf recent introduction)
and I don't have the time to be the only one responsible to maintain
it.

So, either we make it a mandatory check for merging or I'm going to drop it.

Cheers

-- 
Alessandro Pasotti
w3:   www.itopen.it