DOC: Changelog to indicate reason for deps upgrade.

Author: tswast

docs/source/changelog.rst

@@ -5,7 +5,7 @@ Changelog
 ------------------
 - Fix bug with querying for an array of floats (:issue:`123`)
 - Fix bug with integer columns on Windows. Explicitly use 64bit integers when converting from BQ types. (:issue:`119`)
-- Update ``google-cloud-python`` dependency to version 0.32.0+ (:issue:`TBD`)
+- Update ``google-cloud-python`` dependency to version 0.32.0+. Fixes bug caused by breaking change the way ``google-cloud-python`` handles additional configuration argument to ``read_gbq``. (:issue:`152`)
 
 0.3.1 / 2018-02-13
 ------------------