[actions] upgrade composite actions in publish action

Author: ljharb

.github/workflows/npm-publish.yml

@@ -24,10 +24,10 @@ jobs:
 
       - name: Check package version
         id: cpv
-        uses: PostHog/check-package-version@v2
+        uses: ljharb/actions/node/check-package-version@main
 
       - name: Validate package version
-        uses: actions/github-script@v6
+        uses: actions/github-script@v7
         with:
           script: |
             const isNewVersion = `${{ steps.cpv.outputs.is-new-version }}`;
@@ -43,7 +43,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Verify checks passed
-        uses: actions/github-script@v6
+        uses: actions/github-script@v7
         with:
           result-encoding: string
           retries: 3