Feat s3 loading (#176)

* refactor: improved txt reader

* remove print

* feat: load swcs from s3

* feat: read json

* bug: read local txt

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Co-authored-by: anna-grim <anna.grim@alleninstitute.org>

Author: anna-grim

src/segmentation_skeleton_metrics/utils/util.py

@@ -170,7 +170,7 @@ def read_txt(path):
         return read_txt_from_gcs(path)
     else:
         with open(path, "r") as f:
-            return f.read().splitlines()
+            return f.read()
 
 
 def read_zip(zip_file, path):