Attached geocollection for site generic characterization methods

[nrogy]

When a new method is written, a "world" geocollection is automatically attached to it. This is problematic because it can add a geocollection to a site generic method, which leads to unnecessary intersections being calculated in the bw2regional package.

I therefore propose to modify the line

geocollections = {
get_geocollection(third(elem), default_global_location=False) for elem in data
}
In the method.py script for the method write()