fix: include io.Base in the PathType (#2323)

Author: sycai

google/cloud/bigquery/client.py

@@ -139,7 +139,7 @@
 
 iftyping.TYPE_CHECKING: # pragma: NO COVER
 # os.PathLike is only subscriptable in Python 3.9+, thus shielding with a condition.
-PathType=Union[str, bytes, os.PathLike[str], os.PathLike[bytes]]
+PathType=Union[str, bytes, os.PathLike[str], os.PathLike[bytes], io.IOBase]
 _DEFAULT_CHUNKSIZE=100*1024*1024# 100 MB
 _MAX_MULTIPART_SIZE=5*1024*1024
 _DEFAULT_NUM_RETRIES=6