Infer godot pulled version in CI from tag

[piiertho]

#228 currently remove inference of godot version in favor of hardcoded one. This is necessary because godot version is inconsistent and we use 3.3.0 for 3.3 to keep it consistent. The problem is there is no 3.3.0-stable tag on godot's repo. We need to find a way to keep consistency and pull the right version from repo.

[chippmann]

I'm just thinking: If your version suffix is telling the supported godot version, shouldn't we then name our releases after the true godot releases? So in the case where this broke (godot 3.3) shouldn't then be our version for such cases also 1.2.3-3.3 rather than 1.2.3-3.3.0. Because if we are precise; there is no godot 3.3.0.