refactor(command): 'clear' logic refactor

app/src/main/kotlin/command/commands/Clear.kt

@@ -12,7 +12,6 @@ class Clear(
     override val description = "clear colletion"
 
     override fun execute(args: String) {
-        collectionManager.getCollection().clear()
+        collectionManager.clear()
-        io.println(collectionManager.getCollection().toString())
     }
 }

app/src/main/kotlin/manager/CollectionManager.kt

@@ -35,4 +35,8 @@ class CollectionManager(
       """
 
     fun getCollection(): LinkedList<Product> = list
+
+    fun clear() {
+        list.clear()
+    }
 }