Filter Sanic config object to only include configration values in context

[ahopkins]

What does this pull request do?

In the current master, the Sanic integration copies the entire sanic.config.Config object. This object includes some non-configuration values, which are not relevant to capturing in the environment context.

Furthermore, in Sanic v21.9.2, a change was introduced that added a reference to an object that could not be properly copied here: https://github.com/ahopkins/apm-agent-python/blob/060cec6efa22eecfaf773c2df935b6642f841bab/elasticapm/base.py#L456

This resulted in a failure for the response object to populate through the context and ultimately resulting in the error as seen in #1413.

This is a somewhat shortlived issue since the next version of Sanic will remove that. However, it underscores a flaw in this integration in that the only values that should be copied over from the Config object are those that are in all caps.

Therefore, this PR filters the values and will only extend the environment context with the actual configuration values.

Related issues

closes #1413

[apmmachine]

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• Start Time: 2021-11-23T08:09:54.574+0000

• Duration: 33 min 14 sec

• Commit: 81921ee

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Test	Results
Failed	0
Passed	10287
Skipped	9537
Total	19824

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[ahopkins]

$ py.test tests/contrib/sanic

All Sanic tests are passing locally

[beniwohli]

Looks great, thanks @ahopkins for the quick fix!