Set more specific GitHub token permissions on workflows.

.github/workflows/changelog.yaml

@@ -1,4 +1,9 @@
 name: "Ensure labels"
+
+permissions:
+  contents: read
+  pull-requests: read
+
 on: # yamllint disable-line rule:truthy
   pull_request:
     types:

.github/workflows/prepare_release.yml

@@ -1,5 +1,9 @@
 name: Prepare release
 
+permissions:
+  contents: write
+  pull-requests: write
+
 on:
   workflow_dispatch:
     inputs:

.github/workflows/release.yml

@@ -1,6 +1,10 @@
 # Copied from https://github.com/hashicorp/terraform-provider-scaffolding/blob/master/.github/workflows/release.yml
 name: release
 
+permissions:
+  contents: write
+  pull-requests: write
+
 on:
   pull_request:
     types: [closed]

.github/workflows/test.yml

@@ -1,5 +1,8 @@
 name: Run Tests
 
+permissions:
+  contents: read
+
 on:
   pull_request:
     branches:

.github/workflows/test_integration.yml

@@ -1,5 +1,8 @@
 name: Run Integration Tests
 
+permissions:
+  contents: read
+
 on: # yamllint disable-line rule:truthy
   pull_request:
     types: