chore: Update Node.js and pnpm versions in GitHub Actions workflow

- Upgraded pnpm version from 8 to 9.
- Updated Node.js version from 18 to 20.
- Modified the install command to remove the frozen lockfile option.

Author: spences10

.github/workflows/publish.yml

@@ -14,14 +14,14 @@ jobs:
 
       - uses: pnpm/action-setup@v2
         with:
-          version: 8
+          version: 9
 
       - uses: actions/setup-node@v4
         with:
-          node-version: 18
+          node-version: 20
           cache: 'pnpm'
 
-      - run: pnpm install --frozen-lockfile
+      - run: pnpm install
 
       - name: Create Release Pull Request or Publish
         id: changesets