Feature Request: write container id to .tmp file #634

Hi, thank you for awesom development tool.

We use testcontainers in spring-based microservices mostly for launching PostgresQL database. It is enough to use jdbc-url based configuration for us. Also usually we run containers in daemon mode.

Sometimes when I run tests on my machine and then interrupt them (with Ctrl+C, for example), launched container doesn't stop. This is expected because process didn't stop gracefully.

But while it is ok on local machine, it becomes a trouble on CI agents. I noticed many zombie postgres containers on CI agent machines. Probably it hapens because of OutOfMemory on agents (it happens seldom, but it does), probably because of #253 (see the last comment) or something else.

Anyway it seems useful to store launched containers to have an ability to stop them automatically in exceptional cases.