Update dependency boto3 to v1.12.34 (#3251)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [boto3](https://togithub.com/boto/boto3) | patch | `==1.12.33` -> `==1.12.34` |

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### Release Notes

<details>
<summary>boto/boto3</summary>

### [`v1.12.34`](https://togithub.com/boto/boto3/blob/master/CHANGELOG.rst#&#8203;11234)

[Compare Source](https://togithub.com/boto/boto3/compare/1.12.33...1.12.34)

=======

-   api-change:`iot`: [``botocore``] Update iot client to latest version
-   api-change:`mediaconnect`: [``botocore``] Update mediaconnect client to latest version

</details>

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Author: renovate-bot

storage/s3-sdk/requirements.txt

@@ -1 +1 @@
-boto3==1.12.33
+boto3==1.12.34