CI: Do not save ccache for PRs for LINUX_X32

see #14168 which added this for all other builds
see 69dbfad which added the LINUX_X32 build

Author: TimWolla

.github/workflows/push.yml

@@ -140,6 +140,7 @@ jobs:
         with:
           key: "${{github.job}}-${{hashFiles('main/php_version.h')}}"
           append-timestamp: false
+          save: ${{ github.event_name != 'pull_request' }}
       - name: ./configure
         uses: ./.github/actions/configure-x32
         with: