Add missing img alt text in a few spots (#8750)

Author: paulcam206

samples/Templates/Scenarios/FlightDetails.template.json

@@ -96,7 +96,8 @@
 												{
 													"type": "Image",
 													"url": "https://messagecardplayground.azurewebsites.net/assets/smallairplane.png",
-													"height": "16px"
+													"height": "16px",
+													"altText": "Flight to"
 												}
 											],
 											"width": "auto"

source/nodejs/adaptivecards-site/pages/_posts/2020/Community-Call-March.md

@@ -25,7 +25,7 @@ On the **Admin Portal Dashboard**, users can see a summary of card management. U
 
 On the **New Template** page, users can create and edit Adaptive Cards. Users can expect to create Adaptive Cards effortlessly since [Adaptive Cards Designer Tool](https://adaptivecards.io/designer/) is nicely embedded into the ACMS Admin Portal.
 
-![](https://developer.microsoft.com/en-us/office/blogs/wp-content/uploads/2020/03/A-screenshot-1024x522.png)
+![A screenshot of the ACMS New Template page.](https://developer.microsoft.com/en-us/office/blogs/wp-content/uploads/2020/03/A-screenshot-1024x522.pn)
 
 If you click a card on the Dashboard, users will land in **Template View** page where they can check all the details of the card. They can share and publish cards here too! If users **publish** a card template, it can later be retrieved at "run-time" via the ACMS REST API.
 

source/nodejs/adaptivecards-site/themes/adaptivecards/layout/designer.ejs

@@ -195,8 +195,6 @@
 						designer.setCard(JSON.parse(cardXhttp.responseText));
 					}
 
-					// TODO: Talk to David: I want to put the sampleData setter here but it was failing
-
 					history.replaceState(null, null, "<%- config.root %>designer");
 				};
 
@@ -229,6 +227,7 @@
 										"type": "Image",
 										"style": "Person",
 										"url": "${creator.profileImage}",
+										"altText": "${creator.name}",
 										"size": "Small"
 									}
 								],