Context method updateConversation should accept expiration time

[aoberoi]

Description

The conversationContext() built-in middleware, which is added to apps by default, is meant to add a function into the context called updateConversation(state). It allows listeners and middleware to store state that is contextual to the conversation (channel, im, mpim, or group) for use during the handling of a subsequent event.

The App option convoStore allows the user to choose a specific storage provider, as long as it conforms to the ConversationStore interface.

The ConversationStore interface defines the behavior of the set() method such that it can accept an expiration time (expiresAt) in milliseconds. The default implementation, MemoryStore, uses this argument to ensure that subsequent calls to get() don't return the value if it is expired.

The hole here is that updateConversation() doesn't allow the listener or middleware to set an expiration time for the state. It should accept the expiration time as an additional parameter.

Open question: should the additional parameter of updateConversation() be an absolute time (like number of milliseconds since unix epoch), or a relative time (like the number of milliseconds into the future)? I imagine that most developers will have to do some Date math to express a relative time in terms of absolute time, and in that case accepting the relative time directly can offer meaningful convenience.

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.

[seratch]

This issue is a very specific task to update this logic: https://github.com/slackapi/bolt-js/blob/%40slack/bolt%403.3.0/src/conversation-store.ts#L61-L62

[shubhamjajoo]

HI @seratch ,
I have raised PR for this issue here

[seratch]

Fixed by #1221