Replace APNG spec URL

Author: caugner

lint/linter/test-spec-urls.ts

@@ -53,7 +53,6 @@ const specsExceptions = [
   'https://developers.google.com/speed/webp/docs/riff_container',
   'https://developers.google.com/speed/webp/docs/webp_lossless_bitstream_specification',
   'https://jpeg.org/jpeg/',
-  'https://wiki.mozilla.org/APNG_Specification',
   'https://www.adobe.com/devnet-apps/photoshop/fileformatashtml/',
   'https://www.iso.org/standard/89035.html',
   'https://www.rfc-editor.org/rfc/rfc7903',

mediatypes/image/png.json

@@ -50,7 +50,7 @@
         "animation": {
           "__compat": {
             "description": "Animation support (APNG)",
-            "spec_url": "https://wiki.mozilla.org/APNG_Specification#Overview",
+            "spec_url": "https://w3c.github.io/png/#apng-frame-based-animation",
             "support": {
               "chrome": {
                 "version_added": "1"