fix: ensure slash separator when joining URL paths (the base and endpoint URLs) (#4)

Author: lapinek

src/crowdstrike_aidr/_client.py

@@ -190,7 +190,8 @@ def _prepare_url(self, url: str) -> URL:
         merge_url = URL(url)
         if merge_url.is_relative_url:
             base_url = self.base_url
-            merge_raw_path = base_url.raw_path + merge_url.raw_path.lstrip(b"/")
+            # Ensure exactly one slash separator between base and relative paths
+            merge_raw_path = base_url.raw_path.rstrip(b"/") + b"/" + merge_url.raw_path.lstrip(b"/")
             return base_url.copy_with(raw_path=merge_raw_path)
 
         return merge_url