fix: use await instead of waitFor in async tests

[gabrielmer]

Description

In async functions, we should use await instead of waitFor. The usage of waitFor in async tests can generate crashes.

Changes

• change use of waitFor for await in async tests

[github-actions]

You can find the image built from this PR at

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Built from 2ee8958

[github-actions]

You can find the image built from this PR at

quay.io/wakuorg/nwaku-pr:2690-rln-v2

Built from 2ee8958

[Ivansete-status]

LGTM! Thanks! 💯

[SionoiS]

Very nice!

[chaitanyaprem]

Interesting, What is the reason for crash? Is there some bug in waitFor macro or the way use it?

[NagyZoltanPeter]

Sounds very interesting, would be good understand the reason! Thanks!

[gabrielmer]

So in principle,waitFor should not be used in async procedures as it blocks the current thread and it defeats the purpose of async procedures.

Even on its implementation there's a comment stating not to be called from an async proc

https://github.com/status-im/nim-chronos/blob/8a306763cec8105fa83574b56734b0f66823f844/chronos/internal/asyncfutures.nim#L628-L638

Regarding the crash we were having, I haven't yet figured out what exactly was going on that caused it. There were other tests with waitFor being used inside async procedures that did not crash.

In our case, we figured out that the crash happened when trying to write to global variables right after the waitFor, but not sure yet why exactly that's a problem.