Set permissions for GitHub actions

- Included permissions for the action. https://github.com/ossf/scorecard/blob/main/docs/checks.md#token-permissions

https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#permissions

https://docs.github.com/en/actions/using-jobs/assigning-permissions-to-jobs

[Keeping your GitHub Actions and workflows secure Part 1: Preventing pwn requests](https://securitylab.github.com/research/github-actions-preventing-pwn-requests/)

> Restrict the GitHub token permissions only to the required ones; this way, even if the attackers will succeed in compromising your workflow, they won’t be able to do much.

https://www.legitsecurity.com/blog/github-privilege-escalation-vulnerability

Signed-off-by: naveensrinivasan <172697+naveensrinivasan@users.noreply.github.com>

.github/workflows/ruby.yml

@@ -13,6 +13,9 @@ on:
   pull_request:
     branches: [ master ]
 
+permissions:
+  contents: read
+
 jobs:
   test:
 

.github/workflows/stale.yml

@@ -4,9 +4,15 @@ on:
   schedule:
   - cron: "30 1 * * *"
 
+permissions:
+  contents: read
+
 jobs:
   stale:
 
+    permissions:
+      issues: write  # for actions/stale to close stale issues
+      pull-requests: write  # for actions/stale to close stale PRs
     runs-on: ubuntu-latest
 
     steps: