[Enhancement]: Allow running containers with read only root filesystem (`--read-only`)

[nadiamoe]

Proposal

I find testcontainers very useful to run integration tests in environments that are closer to production. One of the things I typically have in production are containers with read-only root filesystem, either through Kubernetes' readOnlyRootFilesystem: true, or through Docker's --read-only.

It would be great if this configuration could be replicated in testcontainers, as it can help catch bugs that other tests do not see: namely, the application trying to write to places where it shouldn't be able to.