[YouTube] Fix testSubscriberCount method of YoutubeChannelExtractorTest.CarouselHeader

The subscriber count is now lower than the expected count as some people
unsubscribed to the Sports system channel. The expected count has been so
lowered.

extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/YoutubeChannelExtractorTest.java

@@ -714,7 +714,7 @@ public class YoutubeChannelExtractorTest {
 
         @Test
         public void testSubscriberCount() throws Exception {
-            ExtractorAsserts.assertGreaterOrEqual(75_000_000, extractor.getSubscriberCount());
+            ExtractorAsserts.assertGreaterOrEqual(70_000_000, extractor.getSubscriberCount());
         }
 
         @Test