Small refactor to DatabaseTest

core/database/src/androidTest/kotlin/com/google/samples/apps/nowinandroid/core/database/dao/DatabaseTest.kt

@@ -44,9 +44,7 @@ internal abstract class DatabaseTest {
     }
 
     @After
-    fun closeDb(){
+    fun teardown() = db.close()
-        db.close()
-    }
 }