chore(.gitignore): add *.mp4 to ignore list

.gitignore

@@ -25,10 +25,10 @@ composer.lock
 # *.svg
 
 # # Videos
-# *.mp4
-# *.avi
-# *.mov
-# *.wmv
-# *.flv
-# *.mkv
-# *.webm
+*.mp4
+*.avi
+*.mov
+*.wmv
+*.flv
+*.mkv
+*.webm