chore: Set permissions for GitHub actions

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: naveensrinivasan <172697+naveensrinivasan@users.noreply.github.com>

.github/workflows/check-licenses.yml

@@ -6,6 +6,9 @@ on:
   pull_request:
     paths:
       - 'vendor'
+permissions:
+  contents: read
+
 jobs:
   build:
     name: Build

.github/workflows/main.yml

@@ -8,6 +8,9 @@ on:
     paths-ignore:
       - 'docs/**'
       - '**.md'
+permissions:
+  contents: read
+
 jobs:
   build:
     name: Build

.github/workflows/wiki.yml

@@ -5,8 +5,13 @@ on:
       - 'docs/*'
     branches:
       - master
+permissions:
+  contents: read
+
 jobs:
   build:
+    permissions:
+      contents: write  # for Git to git push
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@master