feat(test): connecting to PostgreSQL

- rename the database name in the configuration.yaml

src/configuration.rs

@@ -23,3 +23,12 @@ pub fn get_configuration() -> Result<Settings, config::ConfigError> {
 
     settings.try_deserialize::<Settings>()
 }
+
+impl DatabaseSettings {
+    pub fn connection_string(&self) -> String {
+        format!(
+            "postgres://{}:{}@{}:{}/{}",
+            self.username, self.password, self.host, self.port, self.database_name
+        )
+    }
+}