Tests of deprecated features should not print warnings

[kadler]

Is your feature request related to a problem? Please describe.
When running tests in the unit/deprecated directory, deprecation warnings are output. Obviously we know they're deprecated, but we need to ensure that the deprecated functions work the same as they used to for compatibility.

Describe the solution you'd like
Deprecated tests should catch or silence the deprecation warnings. Ideally, tests cases will also ensure that the deprecated functions emit a deprecation warning.

Describe alternatives you've considered
Ignore the output?

[kadler]

Looks like tests could add an event listener for process.on('deprecation', ...) and either ignore the deprecation or validate it. https://www.npmjs.com/package/depd#processondeprecation-fn

After the test case has finished, it should unregister the listener before returning.

[github-actions]

👋 Hi! This issue has been marked stale due to inactivity. If no further activity occurs, it will automatically be closed.