workflows: Limit permission of the makefile.yml action

Suggested by CodeQL.

Signed-off-by: Chuck Lever <[email protected]>

Author: chucklever

.github/workflows/makefile.yml

@@ -6,6 +6,7 @@ jobs:
   build:
 
     runs-on: ubuntu-latest
+    permissions: read-all
     strategy:
       fail-fast: false
       matrix: