chore(deps): update dependency protobuf to v3.17.0 (#885)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [protobuf](https://developers.google.com/protocol-buffers/) | `==3.16.0` -> `==3.17.0` | [![age](https://badges.renovateapi.com/packages/pypi/protobuf/3.17.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/pypi/protobuf/3.17.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/pypi/protobuf/3.17.0/compatibility-slim/3.16.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/pypi/protobuf/3.17.0/confidence-slim/3.16.0)](https://docs.renovatebot.com/merge-confidence/) |

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requirements.txt

@@ -3,7 +3,7 @@ google-api-core==1.26.3
 googleapis-common-protos==1.53.0
 jinja2==3.0.0
 MarkupSafe==2.0.0
-protobuf==3.16.0
+protobuf==3.17.0
 pypandoc==1.5
 PyYAML==5.4.1
 dataclasses==0.6  # TODO(busunkim) remove when 3.6 support is dropped