ci: reduce workflows permissions

Author: cmorten

.github/workflows/publish.yml

@@ -1,5 +1,8 @@
 name: Publish
 
+permissions:
+  contents: read
+
 on:
   release:
     types: [created]

.github/workflows/test-nvda.yml

@@ -1,5 +1,8 @@
 name: Test NVDA
 
+permissions:
+  contents: read
+
 on:
   push:
     branches: [main]

.github/workflows/test-voiceover.yml

@@ -1,5 +1,8 @@
 name: Test VoiceOver
 
+permissions:
+  contents: read
+
 on:
   push:
     branches: [main]

.github/workflows/test.yml

@@ -1,5 +1,8 @@
 name: Test
 
+permissions:
+  contents: read
+
 on:
   push:
     branches: [main]