Bump @actions/attest from 1.6.0 to 2.0.0 (#229)

Bumps [@actions/attest](https://github.com/actions/toolkit/tree/HEAD/packages/attest) from 1.6.0 to 2.0.0.
- [Changelog](https://github.com/actions/toolkit/blob/main/packages/attest/RELEASES.md)
- [Commits](https://github.com/actions/toolkit/commits/HEAD/packages/attest)

---
updated-dependencies:
- dependency-name: "@actions/attest"
  dependency-version: 2.0.0
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -73,7 +73,7 @@
     "@actions/core": "^1.11.1"
   },
   "devDependencies": {
-    "@actions/attest": "^1.6.0",
+    "@actions/attest": "^2.0.0",
     "@eslint/js": "^9.39.1",
     "@types/jest": "^30.0.0",
     "@types/node": "^24.10.1",