Update raven to 6.6.0

[pyup-bot]

There's a new version of raven available.
You are currently using 6.4.0. I have updated it to 6.6.0

These links might come in handy: PyPI | Changelog | Repo

Changelog

6.6.0

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• [Core] Add trimming to breadcrumbs.
• [Core] Improve host message at startup.
• [Core] Update pytest to work on other environments

6.5.0

---

• [Core] Fixed missing deprecation on processors.SanitizePasswordsProcessor
• [Core] Improve exception handling in Serializer.transform
• [Core] Fixed celery.register_logger_signal ignoring subclasses
• [Core] Fixed sanitizer skipping byte instances
• [Lambda] Fixed AttributeError when requestContext not present

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖

[pyup-bot]

Closing this in favor of #162