patch occasional UnicodeEncodeError that occurs with outgoing webhooks

[joeyorlando]

Which issue(s) this PR fixes

Closes #3831

Checklist

• Unit, integration, and e2e (if applicable) tests updated
• Documentation added (or pr:no public docs PR label added if not required)
• CHANGELOG.md updated (or pr:no changelog PR label added if not required)

[joeyorlando]

the exception I was trying to fix, and fully test, here happens rather deep inside the requests package (logs). Rather than trying to figure out what to properly mock there I decided to try out httpretty which according to their docs:

It can be a bit of a hassle to use something like mock.Mock to stub the requests, this can work well for low-level unit tests but when writing functional or integration tests we should be able to allow the http calls to go through the TCP socket module.

HTTPretty monkey patches Python’s socket core module with a fake version of the module.

Because HTTPretty implements a fake the modules socket and ssl you can use write tests to code against any HTTP library that use those modules.

in other words, we don't have to patch requests at all (note: I'm patching requests but w/ the wraps kwarg which basically sets a "spy" on the package and doesn't mock its actual implementation (docs))

[matiasb]

LGTM