Improve secrets storage async methods error handling

[n370]

No description provided.

[radomird]

Hi @n370, did you have anything specific in mind (as the issue lacks description)?

[n370]

Hey @radomird, this part of the codebase has largely changed since the last time I worked on it. Maybe @salmanm and @sameer-coder can help you with the specifics of the implementation but my general idea here was to make sure we were properly handling whatever errors happening while saving and/or retrieving secrets from the secure secrets storage mechanism.

[simoneb]

Let's see if there's anything we should do in this regard or if the code is already good as is after the recent changes, even though I don't think anything has been done explicitly in this regard.

[radomird]

Thanks @n370 I will go through the code and will add were it is needed.

[salmanm]

I had refactored storing secrets and simplified the API there. I think it's in a good shape unless there's anything specific that we'd like to implement.

[radomird]

I've added a few unit tests in the PR, the code however looks good as it handles most of the exceptions I've tried. I did find a minor bug which is fixed in the PR as well.