Get bbox and intersects parameters
.stac_roi(roi)the "roi" parameter defines a region of interest. It can be
an sfc or sf object from sf package, a character with
GeoJSON following the rules from RFC 7946, or a vector
bounding box vector with named XY values
("xmin", "xmax", "ymin", "ymax").
A named list with the values of the intersection and bbox
parameters. If bbox is supplied, the intersection parameter gets
NULL, otherwise bbox gets NULL if intersects is specified.