Images: Update test mock

Author: mdtusz

test/image/mocks/layout_image.json

@@ -8,47 +8,47 @@
   "layout": {
     "images": [
       {
-        "source": "http://www.placekitten.com/100",
+        "source": "https://images.plot.ly/language-icons/api-home/python-logo.png",
         "xref": "paper",
         "yref": "paper",
         "x": 0,
         "y": 0,
-        "width": 0.2,
-        "height": 0.2,
+        "sizex": 0.2,
+        "sizey": 0.2,
         "xanchor": "right",
       "yanchor": "bottom"
       },
       {
-        "source": "http://www.placekitten.com/300",
+        "source": "https://images.plot.ly/language-icons/api-home/js-logo.png",
         "xref": "x",
         "yref": "y",
         "x": 2.5,
         "y": 2,
-        "width": 1,
-        "height": 1,
+        "sizex": 1,
+        "sizey": 1,
         "xanchor": "center",
         "yanchor": "middle",
         "layer": "below"
       },
       {
-        "source": "http://www.placekitten.com/400",
+        "source": "https://images.plot.ly/language-icons/api-home/r-logo.png",
         "xref": "x",
         "yref": "y",
         "x": 1,
         "y": 3,
-        "width": 2,
-        "height": 2,
+        "sizex": 2,
+        "sizey": 2,
         "sizing": "stretch",
         "opacity": 0.4
       },
       {
-        "source": "http://www.placekitten.com/300",
+        "source": "https://images.plot.ly/language-icons/api-home/matlab-logo.png",
         "xref": "x",
         "yref": "paper",
         "x": 2.75,
         "y": 0,
-        "width": 0.5,
-        "height": 1,
+        "sizex": 0.5,
+        "sizey": 1,
         "opacity": 1,
         "xanchor": "left",
         "yanchor": "top"