You can read about it here, if you wish: https://forum.f-droid.org/t/trouble-building-godot-engine-app/14468 he was hitting a time-limit when building…
More specifically:
Although I’m not sure the time limit is the issue. Godot engine and the android export template take about two hours to build in the pipeline, after that the final export command for Carpe Diem is executed. It takes a second or two to load the project and all it’s assets, but then it sits there with no additional output for an hour until the time limit is reached. On my tablet computer with an Intel Atom processor it only takes less than two minutes to export Carpe Diem.