CI permissions

Author: johguenther

.github/workflows/cache-ospray.yml

@@ -1,3 +1,4 @@
+permissions: read-all
 
 on:
   workflow_call:

.github/workflows/ci.yml

@@ -17,6 +17,8 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
+permissions: read-all
+
 jobs:
 
   ## Build Jobs ##

.github/workflows/release.yml

@@ -17,6 +17,8 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
+permissions: read-all
+
 jobs:
 
 ### Build Jobs ###