chore:(lint): remove unnecessary async

Related to #000

What does this MR do and why?

This MR completes !1204 (merged) which removed some async/await non used.

It activates an eslint rule giving errors if function is marked as async not nothing is awaited

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Quality

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Quality checklist

• For the code that this change impacts, I believe that the automated tests validate functionality that is highly important to users. If the existing automated tests do not cover this functionality, I have added the necessary additional tests or I have added an issue to describe the automation testing gap and linked it to this MR.
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