Tear down databases manually feature request

I think a feature that can be added to this library would be to tear down databases manually.

A use case for this would be to do this in the "tear-down" section in testing frameworks. For example, in vitest a possible implementation of this would be:

import {describe, test, beforeAll} from "vitest";
import createDb from "pg-tmp";

describe("Database test", () => {
    beforeAll(async () => {
        const { teardownDb } = await createDb();
        // return cleanup function
        return async () => {
            await teardownDb();
        };
    });
    
    test("specific database tests", () => {
        // tests with the database.
    });
});

This should be easy to implement using the "stop" command already implemented in pg_tmp.sh.

I'd be up to make a PR myself, but I figured I'd get permission first & so forth.

まず、pg_tmp.sh にある既存の stop コマンドと、それを呼び出す Node.js API を読みます。Vitest の例を想定される使用方法として、手動 teardown 関数を createDb からどのように公開するかを定義します。テストのクリーンアップ中に呼び出し側が teardownDb を呼び出せ、既存のデータベース停止動作が再利用されれば完了です。