Remediate Scorecard Token-Permissions findings

This attempts to remediate the problems reported by Scorecard about Token-Permissions

.github/workflows/osv-scanner-unified.yml

@@ -26,13 +26,14 @@ on:
 permissions:
   # Required to upload SARIF file to CodeQL. See: https://github.com/github/codeql-action/issues/2117
   actions: read
-  # Require writing security events to upload SARIF file to security tab
-  security-events: write
   # Read commit contents
   contents: read
 
 jobs:
   scan-scheduled:
+    permissions:
+      # Required for writing security events to upload SARIF file to security tab
+      security-events: write
     if: ${{ github.event_name == 'push' || github.event_name == 'schedule' }}
     # If you want to copy this config, highly suggest pinning this version to a release rather than tracking the main branch
     uses: "google/osv-scanner-action/.github/workflows/osv-scanner-reusable.yml@8bd1ce1c4be9d98053ffd9e6e14585276a36762c" # v1.9.1
@@ -43,6 +44,9 @@ jobs:
         --skip-git
         ./
   scan-pr:
+    permissions:
+      # Required for writing security events to upload SARIF file to security tab
+      security-events: write
     if: ${{ github.event_name == 'pull_request' || github.event_name == 'merge_group' }}
     # If you want to copy this config, highly suggest pinning this version to a release rather than tracking the main branch
     uses: "google/osv-scanner-action/.github/workflows/osv-scanner-reusable-pr.yml@8bd1ce1c4be9d98053ffd9e6e14585276a36762c" # v1.9.1