This URL supports Server Variables and MAY be relative, to indicate that the host location is relative to the
location where the OpenAPI document is being served. Variable substitutions will be made when a variable is named
in {brackets}.
Returns the relative, descendent directory path between this module and other.
Throws if no such path exists.
For example, if module mod1 has path /dir1/mod1.pkl, and module mod2 has path /dir1/dir2/dir3/mod2.pkl,
then mod1.relativePathTo(mod2) will return List("dir2", "dir3").
A common use case is to compute the directory path between a template located at the root of a hierarchy
(say rootModule.pkl) and the currently evaluated module (accessible via the module keyword):
An object representing a Server.