Fix problem with PyInstaller-frozen code and dot in the path (#1994)
Fix problem with PyInstaller-frozen code and dot in the path (#1994)

If `PyInstaller`-frozen application using `patroni` is placed in a location that contains a dot in the path, the `dcs_modules()` function in `patroni.dcs` breaks because `pkgutil.iter_importers()` treats the given path as a package name.

Ref: pyinstaller/pyinstaller#5944

This can be avoided altogether by not passing a path to `iter_importers()`, because `PyInstaller`'s `FrozenImporter` is a singleton and registered as top-level finder.
zalando/patroni,zalando/patroni