Add minimal buffer to the bbox in cases of identical lat or lon values

[kvantricht]

Fix the special case of multiple features being exactly on a lat or lon line, by adding minimal buffer to the identical lat or lon value right before doing the catalogue query.

[HansVRP]

Generally I am confused about the difference in:

if len(shapely_geometries) == 1 and isinstance(shapely_geometries[0], Point):

and the else condition.

The else condition is here constructed to accommodate polygons which are actually points.

Would it not be better then the homogenize this by doing something alike:

 if isinstance(geometry, Point) or (
            isinstance(geometry, (Polygon, MultiPolygon)) and geometry.area == 0
        ):
            geometry = geometry.buffer(0.0001)  # Buffer to create a tiny area

This is some pseudo code, where the point buffer case would be made homogeneous

[HansVRP]

You can avoid some code duplication here by:

# Ensure min/max are not identical
    min_x, min_y, max_x, max_y = bounds
    if min_x == max_x:
        max_x += 0.0001
    if min_y == max_y:
        max_y += 0.0001