Default publish workflow to prerelease (#1233)

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: stephentoub <2642209+stephentoub@users.noreply.github.com>

Author: Copilot

.github/workflows/publish.yml

@@ -10,7 +10,7 @@ on:
         description: "Tag to publish under"
         type: choice
         required: true
-        default: "latest"
+        default: "prerelease"
         options:
           - latest
           - prerelease