chore: add toplevel permissions (open-component-model#1324)

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Signed-off-by: Frederic Wilhelm <frederic.wilhelm@sap.com>

Author: frewilhelm

.github/workflows/jsonschema.yml

@@ -11,6 +11,9 @@ on:
     paths:
       - '**/schemas/*.schema.json'
 
+permissions:
+  contents: read
+
 jobs:
   lint:
     name: Lint

.github/workflows/update-plugin-registry.yaml

@@ -25,6 +25,7 @@ on:
 
 permissions:
   contents: read
+  packages: read
 
 env:
   # Repository selection for checkout