Adding multiple triggers to s3 having different filters and events

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**Is your feature request related to a problem? Please describe.**

I tried to add lambda triggers to my s3 bucket by doing `amplify update storage`, but I can only select one lambda function as a trigger. If you have 3 different functions that have different prefixes and also listens to different events, how do you do that with amplify?

**Describe the solution you'd like**

Allow adding multiple lambda triggers to the storage, or add `Add lambda trigger` option to `amplify update storage`, and be able to add filters to the listener and be able to listen to a specific event.

**Describe alternatives you've considered**

I've done regex against `s3.object.key` but this shouldn't really be the way to go, your listener will run every time even when it does not have to.

**Additional context**

N/A