build(deps): bump undici from 5.28.4 to 6.19.8

Bumps [undici](https://github.com/nodejs/undici) from 5.28.4 to 6.19.8.
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v5.28.4...v6.19.8)

---
updated-dependencies:
- dependency-name: undici
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

package.json

@@ -26,7 +26,7 @@
     "@actions/core": "^1.10.1",
     "@actions/exec": "^1.1.1",
     "@actions/github": "^6.0.0",
-    "undici": "5.28.4"
+    "undici": "6.19.8"
   },
   "devDependencies": {
     "@octokit/webhooks-types": "^7.5.1",