chore(main): release 2.7.1-SNAPSHOT (#830)

:robot: I have created a release *beep* *boop*
---


### Updating meta-information for bleeding-edge SNAPSHOT release.

---
This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please).
6 files changed
tree: bd1f9e0847520796f72ae7280352f8c7aa0406bd
  1. java-core/