Potential fix for code scanning alert no. 6: Workflow does not contain permissions

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
Signed-off-by: mr. m  <91018726+mauro-balades@users.noreply.github.com>

.github/workflows/build.yml

@@ -1,5 +1,8 @@
 name: Zen Release builds
 
+permissions:
+  contents: read
+
 on:
   workflow_dispatch:
     inputs:
@@ -77,6 +80,9 @@ jobs:
           echo "bid=${bdat}" >> $GITHUB_OUTPUT
 
   start-self-host:
+    permissions:
+      contents: read
+      secrets: read
     runs-on: ubuntu-latest
     needs: debug-inputs
     steps:
@@ -102,6 +108,8 @@ jobs:
           rm start.sh || true
 
   check-build-is-correct:
+    permissions:
+      contents: read
     runs-on: ubuntu-latest
     needs: [debug-inputs]
     steps: