chore(ci): tighten workflow token permissions

Author: scop

.github/workflows/check-tag.yml

@@ -5,9 +5,13 @@ on:
     tags:
       - "*"
 
+permissions: {}
+
 jobs:
   check:
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Run checks

.github/workflows/check.yml

@@ -6,9 +6,13 @@ on:
     branches:
       - main
 
+permissions: {}
+
 jobs:
   test:
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       # No caching as we're expected to run rarely