chore(deps): update actions/github-script action to v9

Author: unity-renovate[bot]

.github/workflows/pr-description-validation.yml

@@ -24,7 +24,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Check PR description
-        uses: actions/github-script@v8
+        uses: actions/github-script@v9
         with:
           script: |
             const pr = context.payload.pull_request;

.github/workflows/qa-reviewer-assignment.yml

@@ -23,7 +23,7 @@ jobs:
     steps:
 
       - name: 'Assign QA Team'
-        uses: actions/github-script@v8
+        uses: actions/github-script@v9
         with:
           github-token: ${{ secrets.GH_TOKEN }}
           script: |