chore: Set permissions for GitHub actions (#12626)

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.

- 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/)

Signed-off-by: neilnaveen <42328488+neilnaveen@users.noreply.github.com>

Co-authored-by: Koen Kanters <koenkanters94@gmail.com>

.github/workflows/ci.yml

@@ -2,6 +2,9 @@ name: CI
 
 on: [push, pull_request]
 
+permissions:
+  contents: read
+
 jobs:
   ci:
     runs-on: ubuntu-latest

.github/workflows/stale.yml

@@ -4,8 +4,14 @@ on:
   - cron: "0 0 * * *"
   workflow_dispatch:
 
+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:
     - uses: actions/stale@v5

.github/workflows/update_deps.yml

@@ -4,8 +4,14 @@ on:
   schedule:
   - cron: "0 0 * * 0"
 
+permissions:
+  contents: read
+
 jobs:
   update_deps:
+    permissions:
+      contents: write  # for peter-evans/create-pull-request to create branch
+      pull-requests: write  # for peter-evans/create-pull-request to create a PR
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3