chore: release 1.2.0 (#24)

* updated CHANGELOG.md [ci skip]

* updated setup.py [ci skip]

Author: release-please[bot]

CHANGELOG.md

@@ -4,6 +4,20 @@
 
 [1]: https://pypi.org/project/google-cloud-pubsub/#history
 
+## [1.2.0](https://www.github.com/googleapis/python-pubsub/compare/v1.1.0...v1.2.0) (2020-02-05)
+
+
+### Features
+
+* **pubsub:** add delivery attempt property to message object received by user code ([#10205](https://www.github.com/googleapis/python-pubsub/issues/10205)) ([a0937c1](https://www.github.com/googleapis/python-pubsub/commit/a0937c13107b92271913de579b60f24b2aaac177))
+* add `StreamingPullRequest.client_id` field (via synth) ([199d56a](https://www.github.com/googleapis/python-pubsub/commit/199d56a939bb6244f67138f843dafdd80721f0d3))
+
+
+### Bug Fixes
+
+* **pubsub:** handle None in on response callback ([#9982](https://www.github.com/googleapis/python-pubsub/issues/9982)) ([6596c4b](https://www.github.com/googleapis/python-pubsub/commit/6596c4bae5526d82f5c1b5e0c243b2883404d51f))
+* replace unsafe six.PY3 with PY2 for better future compatibility with Python 4 ([#10081](https://www.github.com/googleapis/python-pubsub/issues/10081)) ([975c1ac](https://www.github.com/googleapis/python-pubsub/commit/975c1ac2cfdac0ce4403c0b56ad19f2ee7241f1a))
+
 ## 1.1.0
 
 12-09-2019 18:51 PST

setup.py

@@ -22,7 +22,7 @@
 
 name = "google-cloud-pubsub"
 description = "Google Cloud Pub/Sub API client library"
-version = "1.1.0"
+version = "1.2.0"
 # Should be one of:
 # 'Development Status :: 3 - Alpha'
 # 'Development Status :: 4 - Beta'