Bump @actions/core from 1.1.0 to 1.2.6

Bumps [@actions/core](https://github.com/actions/toolkit/tree/HEAD/packages/core) from 1.1.0 to 1.2.6.
- [Release notes](https://github.com/actions/toolkit/releases)
- [Changelog](https://github.com/actions/toolkit/blob/main/packages/core/RELEASES.md)
- [Commits](https://github.com/actions/toolkit/commits/HEAD/packages/core)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -18,7 +18,7 @@
   },
   "homepage": "https://github.com/actions/hello-world-javascript-action#readme",
   "dependencies": {
-    "@actions/core": "^1.1.0",
+    "@actions/core": "^1.2.6",
     "@actions/github": "^1.1.0"
   }
 }