ci: Revert changes to cr_preview.yml

Author: xeho91

.github/workflows/cr_preview.yml

@@ -2,7 +2,6 @@ name: Preview
 
 on:
     workflow_call:
-    workflow_dispatch:
 
 defaults:
     run:
@@ -16,7 +15,7 @@ jobs:
         name: pkg.pr.new
         runs-on: macos-latest
         timeout-minutes: 5
-        if: ${{ github.event_name == 'pull_request' || github.event_name == 'workflow_dispatch' }}
+        if: ${{ github.event_name == 'pull_request' }}
         steps:
             # https://github.com/actions/checkout
             - uses: actions/checkout@v4