Changes Manually triggering website publish (#1149)

## Description

Added a workflow dispatch to trigger publiswh workflow manually for
testing purpose, will remove it after testing.
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Author: vineethkuttan

.github/workflows/website-publish.yml

@@ -1,6 +1,7 @@
 name: RNW Website Publish
 
 on:
+  workflow_dispatch:
   push:
     branches:
       - main