Add Quart adapter (resolving #619)

[sonnens]

Add an adapter for Quart ( https://github.com/slackapi/bolt-python/issues/619 )

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

• [ ] slack_bolt.App and/or its core components
• [ ] slack_bolt.async_app.AsyncApp and/or its core components
• [X] Adapters in slack_bolt.adapter
• [ ] Document pages under /docs
• [ ] Others

Requirements (place an x in each [ ])

Please read the Contributing guidelines and Code of Conduct before creating this issue or pull request. By submitting, you are agreeing to those rules.

• [X] I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• [X] I've read and agree to the Code of Conduct.
• [X] I've run ./scripts/install_all_and_run_tests.sh after making the changes.

[CLAassistant]

All committers have signed the CLA.

[seratch]

Hi @sonnens, thanks for submitting the PR!

There are a few things that we would like you to add:

• Add qaurt dependency to run CI builds here
• Add unit tests and examples like https://github.com/slackapi/bolt-python/pull/614 nicely did

As I mentioned at https://github.com/slackapi/bolt-python/issues/619#issuecomment-1073182688, we need your (and/or other community members') help for this addition more than usual. It'd be appreciated if you could understand this.