fix: wrong attribute name used for PersistDict

Signed-off-by: thiswillbeyourgithub <26625900+thiswillbeyourgithub@users.noreply.github.com>

Author: thiswillbeyourgithub

wdoc/utils/customs/compressed_embeddings_cache.py

@@ -73,7 +73,7 @@ def mget(self, keys: Sequence[str]) -> List[Optional[bytes]]:
             If a key is not found, the corresponding value will be None.
         """
         values = self.pdi.__getitems__(keys)
-        values = [v if v is not self.pdi.missing_value else None for v in values]
+        values = [v if v is not self.pdi.__missing_value__ else None for v in values]
         return values