logs-content: Fixed post being added twice on add due to race condition between websocket and mutation return.

marko/page/logs-content/components/page/component.js

@@ -111,6 +111,11 @@ module.exports = class {
   }
 
   postAdded(post) {
+    // Stop duplicates in case of race condition.
+    if (this.state.log.posts.find(p => p.id === post.id)) {
+      return
+    }
+
     this.state.log.posts = this.state.log.posts.concat([post])
     this.state.log = Object.assign({}, this.state.log)    
   }