Fix #5063: Support downloading ArtStation video clips.

app/logical/source/extractor/art_station.rb

@@ -57,8 +57,6 @@ class Source::Extractor
         if asset[:asset_type] == "image"
           asset_url(asset[:image_url])
         elsif asset[:asset_type] == "video_clip"
-          next # XXX Skip for now; actually downloading these videos requires bypassing a Cloudflare captcha.
-
           url = Nokogiri::HTML5.parse(asset[:player_embedded]).at("iframe").attr("src")
           next if url.nil?
 

test/unit/sources/art_station_test.rb

@@ -72,7 +72,7 @@ module Sources
     end
 
     context "An ArtStation post with images and videos" do
-      strategy_should_work( # XXX Broken by Cloudflare captcha
+      strategy_should_work(
         "https://www.artstation.com/artwork/0nP1e8",
         image_urls: %w[
           https://cdn.artstation.com/p/assets/images/images/040/979/418/original/yusuf-umar-workout-10mb.gif?1630425406
@@ -91,7 +91,8 @@ module Sources
     context "An ArtStation video url" do
       strategy_should_work(
         "https://cdn-animation.artstation.com/p/video_sources/000/466/622/workout.mp4",
-        image_urls: ["https://cdn-animation.artstation.com/p/video_sources/000/466/622/workout.mp4"]
+        image_urls: ["https://cdn-animation.artstation.com/p/video_sources/000/466/622/workout.mp4"],
+        download_size: 377_969,
       )
     end