fix: update url in setup.py (#13)

Fixes #12

Author: jayvdb

setup.py

@@ -73,7 +73,7 @@
     author="Google LLC",
     author_email="[email protected]",
     license="Apache 2.0",
-    url="https://github.com/GoogleCloudPlatform/python-texttospeech",
+    url="https://github.com/googleapis/python-texttospeech",
     classifiers=[
         release_status,
         "Intended Audience :: Developers",