Bump @actions/core from 1.2.6 to 1.9.1 in /build (#23040)

Bumps [@actions/core](https://github.com/actions/toolkit/tree/HEAD/packages/core) from 1.2.6 to 1.9.1.
- [Changelog](https://github.com/actions/toolkit/blob/main/packages/core/RELEASES.md)
- [Commits](https://github.com/actions/toolkit/commits/HEAD/packages/core)

---
updated-dependencies:
- dependency-name: "@actions/core"
  dependency-type: direct:development
...

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build/package.json

@@ -3,7 +3,7 @@
   "version": "1.0.0",
   "license": "MIT",
   "devDependencies": {
-    "@actions/core": "1.2.6",
+    "@actions/core": "1.9.1",
     "@actions/github": "2.1.1",
     "@azure/cosmos": "^3.14.1",
     "@azure/identity": "^3.1.4",