deps: update actions/github-script action to v8

Author: renovate-bot

.github/workflows/approve-readme.yaml

@@ -21,7 +21,7 @@ jobs:
     runs-on: ubuntu-latest
     if: github.repository_owner == 'googleapis' && github.head_ref == 'autosynth-readme'
     steps:
-      - uses: actions/github-script@v7
+      - uses: actions/github-script@v8
         with:
           github-token: ${{secrets.YOSHI_APPROVER_TOKEN}}
           script: |

.github/workflows/auto-release.yaml

@@ -24,7 +24,7 @@ jobs:
     runs-on: ubuntu-latest
     if: contains(github.head_ref, 'release-please')
     steps:
-    - uses: actions/github-script@v7
+    - uses: actions/github-script@v8
       with:
         github-token: ${{secrets.YOSHI_APPROVER_TOKEN}}
         debug: true