.github: restrict workflow permissions

As suggested by CodeQL scanning.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

.github/workflows/build.yml

@@ -10,6 +10,9 @@ on:
   pull_request:
     types: [opened, synchronize, reopened, labeled]
 
+permissions:
+  contents: read
+
 concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref || github.ref }}
   cancel-in-progress: true

.github/workflows/coverity.yml

@@ -6,6 +6,9 @@ on:
       - 'dev'
   workflow_dispatch:
 
+permissions:
+  contents: read
+
 env:
   PROJECT_NAME: finit
   CONTACT_EMAIL: troglobit@gmail.com

.github/workflows/release.yml

@@ -5,6 +5,9 @@ on:
     tags:
       - '[0-9]+.[0-9]+*'
 
+permissions:
+  contents: write
+
 jobs:
   release:
     name: Build and upload release tarball

.github/workflows/weekly.yml

@@ -7,6 +7,9 @@ on:
     - cron: '0 0 * * 0'
   workflow_dispatch:
 
+permissions:
+  contents: read
+
 jobs:
   schedule:
     runs-on: ubuntu-latest