fix: wrong ver name for isPhoenixEmbeddedIframe in md live preview

Author: abose

src/extensionsIntegrated/Phoenix-live-preview/markdown.html

@@ -29,7 +29,7 @@
                 window.__PHOENIX_EMBED_INFO = {
                     isTauri: event.data.isTauri,
                     platform: event.data.platform,
-                    isEmbeddedIframe: event.data.isEmbeddedIframe
+                    isPhoenixEmbeddedIframe: event.data.isPhoenixEmbeddedIframe
                 };
             } else if(event.data.type === "_TEST_FOCUS_CLICK") { // for integ tests
                 document.body.click();