fix: comma and restore sample_songs

scripts/sample_songs.json

@@ -1,3 +1,8 @@
 {
-    "dancing_queen": "https://www.youtube.com/watch?v=3qiMJt-JBb4"
+    "dancing_queen": "https://www.youtube.com/watch?v=3qiMJt-JBb4",
+    "bohemian_rhapsody": "https://www.youtube.com/watch?v=yk3prd8GER4",
+    "i_want_it_that_way": "https://www.youtube.com/watch?v=qjlVAsvQLM8",
+    "let_it_be": "https://www.youtube.com/watch?v=FIV73iG_e5I",
+    "viva_la_vida": "https://www.youtube.com/watch?v=a1EYnngNHIA",
+    "zombie": "https://www.youtube.com/watch?v=8sM-rm4lFZg"
 }

scripts/separate_songs.json

@@ -4,5 +4,5 @@
     "Backstreet_Boys_-_I_Want_It_That_Way": ["https://www.youtube.com/watch?v=qjlVAsvQLM8", 43],
     "The_Beatles_-_Let_It_Be": ["https://www.youtube.com/watch?v=FIV73iG_e5I", 82],
     "Coldplay_-_Viva_La_Vida": ["https://www.youtube.com/watch?v=a1EYnngNHIA", 7],
-    "The_Cranberries_-_Zombie": ["https://www.youtube.com/watch?v=8sM-rm4lFZg", 82],
+    "The_Cranberries_-_Zombie": ["https://www.youtube.com/watch?v=8sM-rm4lFZg", 82]
 }