Add workflow for automatic issue deduplication (#41942)

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fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request
Tested this in my fork, this'll run the dedup AI model on any new issue
that's been filed or re-opened. If it finds a duplicate, it'll label it
with "duplicate" and comment which issues it dupes to. This won't close
the issue.

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## PR Checklist

- [ ] Closes: #xxx
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

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or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

.github/workflows/automatic-issue-deduplication.yml

@@ -0,0 +1,19 @@
+name: Automatic New Issue Deduplication
+on:
+  issues:
+    types: [opened, reopened]
+permissions:
+  models: read
+  issues: write
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.issue.number }}
+  cancel-in-progress: true
+jobs:
+  deduplicate:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Run Deduplicate Action
+        uses: pelikhan/action-genai-issue-dedup@v0
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          label_as_duplicate: true