chore: release 0.59.0 (googleapis#1126)

Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>

Author: release-please[bot]

CHANGELOG.md

@@ -1,6 +1,13 @@
 # Changelog
 
 
+## [0.59.0](https://www.github.com/googleapis/gapic-generator-python/compare/v0.58.4...v0.59.0) (2022-01-10)
+
+
+### Features
+
+* add snippet index ([#1121](https://www.github.com/googleapis/gapic-generator-python/issues/1121)) ([55d2bc6](https://www.github.com/googleapis/gapic-generator-python/commit/55d2bc6580e5db0f837de1b245533a8f1f2e9beb))
+
 ### [0.58.4](https://www.github.com/googleapis/gapic-generator-python/compare/v0.58.3...v0.58.4) (2021-12-30)