chore(deps): bump @actions/core in /.github/workflows/scripts/mailchimp

Bumps [@actions/core](https://github.com/actions/toolkit/tree/HEAD/packages/core) from 1.6.0 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:production
...

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

.github/workflows/scripts/mailchimp/package.json

@@ -3,7 +3,7 @@
   "description": "This code is responsible for scheduling an email campaign. This file is centrally managed in https://github.com/asyncapi/.github/",
   "license": "Apache 2.0",
   "dependencies": {
-    "@actions/core": "1.6.0",
+    "@actions/core": "1.9.1",
     "@mailchimp/mailchimp_marketing": "3.0.74"
   }
 }