Amplify function specify source location

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** Which Category is your question related to? **
Amplify Cli functions
** What AWS Services are you utilizing? **
Appysync, dynamo, lambda
** Provide additional details e.g. code snippets **
I couldn't find my answer in the docs for amplify or in the more general aws docs for functions.

I have an amplify project with a function that I originally created with all the code in `src/` but I have now added webpack to package up the function code which outputs to `src/bin`. How do I tell amplify to target that specific directory to create the zip that it puts in the `dist/` dir?
i.e I would like to zip the output of webpack not the src.

It looks like it runs my script `"amplify:my-function": "npm run lint && npm run webpack"`

I tried changing the lambda function aws:asset:path in the medatadate section in cloud formation template but I don't think its used here