ci: declare read-only token permissions on test workflow

Signed-off-by: Arpit Jain <arpitjain099@gmail.com>

Author: arpitjain099

.github/workflows/pythonpackage.yml

@@ -2,6 +2,9 @@ name: Test package
 
 on: [push, pull_request]
 
+permissions:
+  contents: read
+
 jobs:
   build:
     runs-on: ${{ matrix.os }}