Implement adapter.close function

[stevebaum23]

• When the close function is called it will (p)unsubscribe from the channels it (p)subscribed to in the constructor.
• Added a test to verify that channels are being unsubscribed from when close is called.

This is implemented in conjunction with socketio/socket.io#4602 to fix #480.

[stevebaum23]

Not sure why the test is failing here. I've tried running the tests locally using docker instances of redis v3 and v4 and they always pass. I pushed a new commit that adds a delay before starting the test. My theory is that not all the subscriptions have completed by the time test starts to run.

[stevebaum23]

@darrachequesne Would you mind kicking off the tests again, to see if they pass? I don't think I can kick them off.

[stevebaum23]

@darrachequesne Sorry, I had a formatting issue that caused the tests to not run. When you get a chance, can you kick them off again? Thanks!

[stevebaum23]

@darrachequesne I sorted the test out. I wasn't running against the latest version of redis. 🤦 These should pass now.

[stevebaum23]

@darrachequesne If you get a chance, can you kick off the tests again?

[darrachequesne]

Released in version 8.1.0. Thanks a lot!