feat(core): change default api_request() timeout to non-None

[plamut]

Closes#10217.

As discussed - we want to have a non-None default timeout, but still allow overriding it with None if somebody wants so.

PR checklist

• Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• Ensure the tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)