reverse checks to see the other path

Author: Mpdreamz

.github/workflows/preview-build.yml

@@ -60,14 +60,14 @@ jobs:
     steps:
       - name: Not a push event
         id: event-check
-        if: contains(fromJSON('["merge_group", "pull_request", "pull_request_target"]'), github.event_name)
+        if: contains(fromJSON('["merge_group", "push", "pull_request_target"]'), github.event_name)
         # ensure we emit static output to simplify our checks in the build step
         run: |
           echo "content-source-match=true" >> $GITHUB_OUTPUT
           echo "content-source-name=next" >> $GITHUB_OUTPUT
       - name: Match for push events
         id: match
-        if: contains(fromJSON('["push"]'), github.event_name)
+        if: contains(fromJSON('["pull_request"]'), github.event_name)
         uses: elastic/docs-builder/actions/assembler-match@main
         with:
           ref_name: ${{ github.event.ref_name }}