Added suspendForMs to @RetryingTest

[mathieufortin01]

fixes #407
Simple implementation just to get the discussion going.

• Added suspendForMs param to @RetryingTest
• Added a few tests. These are based on timing, so theres a risk of flakiness.

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[tflatter-exaring]

you should not wait, if this is the first execution of the test

[nipafx]

@mathieufortin01, thank you for the PR, I really appreciate it! If you've observed the project a bit, you know we occasionally take some time, but we're on it now.

Can you merge main, resolve the conflict and take a look at these comments?

[mathieufortin01]

@nipafx Thanks for the review. Addressed all comments. Let me know.

[nipafx]

I like this little refactoring! 👍🏾

[nipafx]

Looks great, thank you @mathieufortin01! I was about to merge when I noticed that you didn't add yourself to the README - we like to list all contributors there to publicly shame thank 😉 them, but this is by no means obligatory if you prefer not to be mentioned. Let me know either way.

[mathieufortin01]

@nipafx here you go. let the shame begin.

[nipafx]

Commit message:

Add option to suspend between retrying tests (#407 / #604)

Retrying tests may be flaky because of issues with external services.
The chance that they recover and behave correctly on the next try may
improve if there's a (short) pause between the test runs. This change
adds an option to suspend for a fixed time span (in milliseconds)
betweet tries.

The implemenation simply lets the executing thread sleep, which
isn't ideal. It would be much better if there were a way to schedule
the next execution for later and use the thread to execute other
tests in between, but Jupiter doesn't offer an API for that.

Closes: #407
PR: #604

[nipafx]

Thanks a lot @mathieufortin01, for your contribution and patience! 👏🏾👏🏾👏🏾