chore: Sync common workflows

This is an automated sync of common workflows for this organization.
The upstream source is:
shaka-project/shaka-github-tools@f0ad5ac

.github/workflows/sync-labels.yaml

@@ -16,6 +16,11 @@ on:
 jobs:
   sync-labels:
     runs-on: ubuntu-latest
+
+    permissions:
+      # "Write" to Issues to manage labels for the repo
+      issues: write
+
     steps:
       - name: Checkout code
         uses: actions/checkout@v4

.github/workflows/update-issues.yaml

@@ -15,6 +15,13 @@ permissions:
 jobs:
   update-issues:
     runs-on: ubuntu-latest
+
+    permissions:
+      # "Write" to Issues to add labels, milestones, comments, etc.
+      issues: write
+      # "Write" to Pull Requests for the same.
+      pull-requests: write
+
     steps:
       - name: Checkout code
         uses: actions/checkout@v4