wrapper for API base url retrieval

src/delta_barth/management.py

@@ -34,3 +34,7 @@ def set_base_url(
     base_url: str,
 ) -> None:  # pragma: no cover
     SESSION.set_base_url(base_url=base_url)
+
+
+def get_base_url() -> str:  # pragma: no cover
+    return SESSION.base_url