Allow delay to be configurable for tests

[huwshimi]

What are the steps to reproduce this issue?

1. Generate the API with mocks.
2. Create tests using the mocks.

What happens?

Depending on the delay you set in your config, either your tests are very slow or you have to have a very short delay when simulating the API in a browser.

What were you expecting to happen?

Have a way to either set the delay separately for tests, or set the delay at runtime.

Any logs, error output, etc?

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Any other comments?

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What versions are you using?

Operating System: …
Package Version: …
Browser Version: …