Import "Fix some typos (it's vs its)" (#175)

Summary:
Original author: noahsark769

Closes https://github.com/facebook/Sonar/pull/175

Reviewed By: jknoxville

Differential Revision: D8989724

fbshipit-source-id: 8e1c09196b0c6c0d0fb0446a2a4a595d09f21652

src/plugins/layout/index.js

@@ -571,7 +571,7 @@ export default class Layout extends SonarPlugin<InspectorState> {
       // expand current element
       const children = await this.setElementExpanded(key, true, ax);
 
-      // and add it's children to the queue
+      // and add its children to the queue
       for (const child of children) {
         keys.push(child.id);
       }