add decoder_fast to the list

Author: sungwy

pyiceberg/avro/decoder_fast.pyi

@@ -17,6 +17,8 @@
 
 from pyiceberg.avro.decoder import BinaryDecoder
 
+__all__: list[str] = []
+
 class CythonBinaryDecoder(BinaryDecoder):
     def __init__(self, input_contents: bytes) -> None:
         pass

pyiceberg/avro/decoder_fast.pyx

@@ -23,6 +23,8 @@ from libc.stdint cimport uint64_t, int64_t
 
 import array
 
+__all__ = []
+
 
 cdef extern from "decoder_basic.c":
   void decode_zigzag_ints(const unsigned char **buffer, const uint64_t count, uint64_t *result);