[mod] result_templates/videos.html: replace embedded HTML by data_src

Embedded HTML breaks SearXNG architecture.  To modularize, HTML is generated in
the templates (oscar & simple) and result parameter 'embedded' is replaced by
'data_src', an URL for embedded content (<iframe>).

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

searx/engines/youtube_api.py

@@ -26,13 +26,6 @@ api_key = None
 # search-url
 base_url = 'https://www.googleapis.com/youtube/v3/search'
 search_url = base_url + '?part=snippet&{query}&maxResults=20&key={api_key}'
-
-embedded_url = (
-    '<iframe width="540" height="304" '
-    + 'data-src="https://www.youtube-nocookie.com/embed/{videoid}" '
-    + 'frameborder="0" allowfullscreen></iframe>'
-)
-
 base_youtube_url = 'https://www.youtube.com/watch?v='
 
 
@@ -77,8 +70,6 @@ def response(resp):
 
         url = base_youtube_url + videoid
 
-        embedded = embedded_url.format(videoid=videoid)
-
         # append result
         results.append(
             {
@@ -87,7 +78,7 @@ def response(resp):
                 'content': content,
                 'template': 'videos.html',
                 'publishedDate': publishedDate,
-                'embedded': embedded,
+                'data_src': "https://www.youtube-nocookie.com/embed/" + videoid,
                 'thumbnail': thumbnail,
             }
         )