Update Phase1.md

com.unity.perception/Documentation~/Tutorial/Phase1.md

 * `x` and `y`: Pixel coordinates of the top-left corner of the object's bounding box (measured from the top-left corner of the image)
 * `width` and `height` of the object's bounding box
 
+* **Action**: Review the JSON meta-data and the images captured for the first annotated frame, and verify that the objects within them match. 
 
 ### <a name="step-7">Step 7: Verify Data Using Dataset Insights</a>