Potential fix for code scanning alert no. 2: Workflow does not contain permissions (#60)

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

Author: sjentoft

.github/workflows/R-CMD-check.yaml

@@ -7,6 +7,8 @@ on:
     branches: [main, master]
 
 name: R-CMD-check
+permissions:
+  contents: read
 
 jobs:
   R-CMD-check: