Add conditional support for AVIF in Edge Dev/Canary

MicrosoftEdge/Status#723

features-json/avif.json

@@ -79,7 +79,9 @@
       "111":"n",
       "112":"n",
       "113":"n",
-      "114":"n"
+      "114":"n",
+      "115":"n",
+      "116":"n d #6"
     },
     "firefox":{
       "2":"n",
@@ -564,7 +566,8 @@
     "2":"Supports still images. Animated image sequences are not supported.",
     "3":"Only available on macOS 13 Ventura or later.",
     "4":"Does not support images with noise synthesis.",
-    "5":"Supports only still images by default. Animated image sequences can be enabled via the `image.avif.sequence.enabled` pref in `about:config`."
+    "5":"Supports only still images by default. Animated image sequences can be enabled via the `image.avif.sequence.enabled` pref in `about:config`.",
+    "6":"Can be enabled in Edge on Windows 10 or later by installing the [AV1 Video Extension from the Microsoft Store](https://www.microsoft.com/store/productId/9MVZQVXJBQ9V)"
   },
   "usage_perc_y":82.33,
   "usage_perc_a":1.64,