Create stalebot.yml, update contributors to explain its existence (#9264

)

* Create stalebot.yml

* Update CONTRIBUTING.md

description of stalebot

* Update stalebot.yml

* Update stalebot.yml

remove whitespace to pass linting

---------

Co-authored-by: AbdulFattaah Popoola <abdulapopoola@github.com>

.github/workflows/stalebot.yml

@@ -0,0 +1,26 @@
+name: Close stale Issues and PRs
+
+permissions:
+  issues: write
+  pull-requests: write
+
+on:
+  schedule:
+  - cron: "00 0 * * *" # runs at 00:00 daily
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/stale@v9.0.0
+      name: Clean up stale PRs and Issues
+      with:
+        stale-pr-message: "👋 This pull request has been marked as stale because it has been open for 2 years with no activity. You can: comment on the PR or remove the stale label to hold stale off for a while, add the `Keep` label to hold stale off permanently, or do nothing. If you do nothing, this pull request will be closed eventually by the stale bot. Please see CONTRIBUTING.md for more policy details."
+        stale-issue-message: "👋 This issue has been marked as stale because it has been open for 2 years with no activity. You can: comment on the issue or remove the stale label to hold stale off for a while, add the `Keep` label to hold stale off permanently, or do nothing. If you do nothing, this issue will be closed eventually by the stale bot. Please see CONTRIBUTING.md for more policy details."
+        stale-pr-label: "Stale"
+        exempt-pr-labels: "Keep" # a "Keep" label will keep the PR from being closed as stale
+        days-before-pr-stale: 730 # when the PR is considered stale
+        days-before-pr-close: 60 # when the PR is closed by the bot,
+        days-before-issue-stale: 730 # prevents issues from being tagged by the bot
+        days-before-issue-close: 60 # prevents issues from being closed by the bot
+        ascending: true

CONTRIBUTING.md

@@ -48,3 +48,7 @@ is a clearer interface between core and the language-specific tooling.
 
 Our goal is make it easier to create and test Dependabot extensions so there is a paved path for running additional
 ecosystems in the future.
+
+## Stalebot
+
+We have begun using a [Stalebot action](https://github.com/actions/stale) to help keep the Issues and Pull requests backlogs tidy. You can see the configuration [here](.github/workflows/stalebot.yml). If you'd like to keep an issue open after getting a stalebot warning, simply comment on it and it'll reset the clock.