[Feature]: Add async-diesel to shuttle-aws-rds about shuttle

[sourabpramanik]

I would like to work on it

[jonaro00]

@edgerunnergit Running an RDS resource on a local run essentially starts a dummy one for you (a local docker container). If all the feature flags work against local dbs, it should be a sufficient implementation.

[edgerunnergit]

@sourabpramanik woul definitely like to work on it. (i have already started experimenting with it)

[edgerunnergit]

As it's been a while I wanted to work on the issue.

Also I do not have access to an rds instance for testing purposes. Would it be possible to provide a dummy one?
I could also create a draft PR if it helps.

Here's what I initially came up with

[sourabpramanik]

@edgerunnergit let me know if you are going to work on this. I was not having enough bandwidth last month to work on this but now I can wrap this week.