Add endpoints for calls.* apis and Type: call in blockkit

[winston-stripe]

Implement the API methods for the Calls API in Slack https://api.slack.com/apis/calls

Implemented methods

• calls.add - Indicate a new call has been started
• calls.end - Indicate to slack that the call has ended
• calls.info - Get information about an ongoing slack call object
• calls.update - update call information
• calls.participants.add
• calls.participants.remove

Additionally, I've added the minimal version of Block{Type: "call", CallID: string} which slack recommends/requires be posted back to the channel https://api.slack.com/apis/calls#post_to_channel.

All implemented functionality is publicly documented. There appear to be additional attributes on the type: call block, however those appear to be internal values for slack's rendering, so I have left them out. See this gist for specific responses https://gist.github.com/winston-stripe/0cac608bd63b42d73a352be53577f7fd

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PR preparation

Run make pr-prep from the root of the repository to run formatting, linting and tests.

Should this be an issue instead

• is it a convenience method? (no new functionality, streamlines some use case)
• exposes a previously private type, const, method, etc.
• is it application specific (caching, retry logic, rate limiting, etc)
• is it performance related.

API changes

Since API changes have to be maintained they undergo a more detailed review and are more likely to require changes.

• no tests, if you're adding to the API include at least a single test of the happy case.
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• in library cache for users. caches are use case specific.
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[winston-stripe]

Oddly, I have no idea why the lint step is failing. Downloaded and ran golangci-lint run locally and everything ran without a hitch. Maybe some weird bad caching or some unexpected actions interaction? Fwiw, when looking through their docs, I did notice that

v3.0.0+ requires explicit setup-go installation step prior to using this action: uses: actions/setup-go@v3

Still no idea otherwise esp since master is passing, i'm fully based off of master, and all failing files are other ones I didn't touch here 😕.

[winston-stripe]

Thanks @kanata2 for fixing the repo's linting check in #1194! rebased off master and everything is passing now

[winston-stripe]

bump: @kanata2 is it possible to get a 👀 on this?

[lorenzoaiello]

Thanks for the awesome addition @winston-stripe ! I've left just a few minor items for you to review. I'm excited to get this merged and see what folks build with this.

[github-actions]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[winston-stripe]

ack, finally have time to look back into this. Hopefully get it cleaned up again today. Thanks for the feedback @lorenzoaiello!

[winston-stripe]

@lorenzoaiello I updated the params + s/users/participants/ for the Go side of the API to make it a bit more clear & consistent. LMK your thoughts :)

[lorenzoaiello]

Looks good, thank you for the additions!