Add GitHub Actions job for better triage process

[srajiang]

Summary

This PR adds an action which will automate stale-ing and closing inactive issues. This action does not impact:

• open PRs
• issues attached to any release milestones, e.g. 3.x.
• issues explicitly tagged with the label auto-triage-skip.

For inactive issues:

• At 30-days old w/ no activity: The action will mark the issue with auto-triage-stale label and post a message in thread notifying all participants that after 10 further days w/out activity, the issue will be closed.
• At 10 days after marked stale w/ no activity: Action will close the issue

For maintainers, and for the wider community:

👋 The goal with these changes is to make sure that issues are staying updated, as activity is the best indicator that it will be resolved! That means, if more info is needed and you need a bit more time to investigate, or if we need more time to investigate an issue internally, the best way to keep the issue updated is to post a comment!

Todo:

• Reviewers - is weekly on Sundays a good cadence?
• After review, merge to main and do a debug run
• Update debug-only: false

Requirements (place an x in each [ ])

• 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.

[codecov]

Codecov Report

Merging #1213 (2beece7) into main (020c44f) will not change coverage.
The diff coverage is n/a.

❗ Current head 2beece7 differs from pull request most recent head 7746a8f. Consider uploading reports for the commit 7746a8f to get more accurate results

@@           Coverage Diff           @@
##             main    #1213   +/-   ##
=======================================
  Coverage   73.20%   73.20%           
=======================================
  Files          17       17           
  Lines        1437     1437           
  Branches      431      431           
=======================================
  Hits         1052     1052           
  Misses        300      300           
  Partials       85       85           

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[seratch]

Thanks for working on this! I left a few comments.

[seratch]

If we use the term "auto-triage", consistently having the term in the labels may be easier to understand. Like this:

• stale-issue-label: auto-triage-stale
• exempt-issue-labels: auto-triage-skip

What do you think?

[srajiang]

I like that - I will add those updates.

[seratch]

10 days sounds reasonable 👍

[seratch]

being inactive for 10 days with no further update.

In this situation, the issue should be inactive for 40+ days (30 days before being marked as stale, and then 10 days until closing), right?

Also, (perhaps, other maintainers can come up with a better sentence but) using a bit more friendly message like "As this issue has been inactive for more than one month, let us close this. Thanks again for writing in here!" or so may be fine.

[srajiang]

How about:
"As this issue has been inactive for more than one month, we will be closing it. Thanks again for writing in!"

[seratch]

Thanks, looks great 👍

[filmaj]

Echoing @seratch's comments, but LGTM in general!

[seratch]

@srajiang when to remove this line?

[srajiang]

Very shortly - I'm reviewing the output of the test run now. If all clear on that and it's doing what I think it should be doing, we can remove it. I won't include this line for PRs in other repos.

[srajiang]

The output is here: https://github.com/slackapi/bolt-js/runs/4257717061?check_suite_focus=true in case you'd like to review the triage results (when performed in debug mode).

[mwbrooks]

Looks awesome! Nice work.

[mwbrooks]

Do we want to add a CTA that the issue can be re-opened if anyone wants? I'm cool either way.