App start() does not account for AWSLambdaReceiver return type

[srajiang]

Description

App::start return type does not account for AWSLambdaReceiver, causing TS to complain.

Related: #1034

app.start's return type is ReturnType<HTTPReceiver['start']>, which is Promise<Server> (code).

When using bolt-js AWSLambdaReceiver in Typescript, the return type of App::start causes the TS compiler to complain. Users following along with the deploying to aws serverless sample code see this:

With correct return type Promise<AWSHandler> as defined here, this issue goes away.

What type of issue is this? (place an x in one of the [ ])

• bug
• enhancement (feature request)
• question
• documentation related
• example code related
• testing related
• discussion

Requirements (place an x in each of the [ ])

• I've read and understood the Contributing guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.
• I've searched for any related issues and avoided creating a duplicate issue.

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Bug Report

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Reproducible in:

package version: 3.5.0

node version:

OS version(s):