Update CHANGELOG.rst

fix minor typo

Author: jodoglevy

CHANGELOG.rst

@@ -12,7 +12,7 @@ The format is based on `Keep a Changelog <http://keepachangelog.com/>`_.
  Added
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-* An UploadManager class to better support large object uploads though multipart and parallel operations.
+* An UploadManager class to better support large object uploads through multipart and parallel operations.
 * Support for object storage pre-authenticated requests and public buckets.
 * Support for load balancing service.
 * Support for nested instance metadata operations.