[bigs] Fixed a bug caused by a type error (#696)

* 修正了因为类型错误导致的bug

* remove ds_store

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Co-authored-by: Cheng <cheng@ChengdeMacBook-Air.local>

asteroid/data/librimix_dataset.py

@@ -89,7 +89,7 @@ def __getitem__(self, idx):
         sources_list = []
         # If there is a seg start point is set randomly
         if self.seg_len is not None:
-            start = random.randint(0, row["length"] - self.seg_len)
+            start = random.randint(0, int(row["length"] - self.seg_len))
             stop = start + self.seg_len
         else:
             start = 0