docs: example for configuring a custom DockerContainer

[vemonet]

Current examples for running a DockerContainer are all using with DockerContainer (3 examples out of 3).

But this is not the right way when someone wants to add some custom configuration (expose a port, define an environment variable), which is quite a regular use-case.

Newcomers reading this docs might get confused and will need to go through the process of finding out how to do this properly outside of the docs (e.g. this guy here https://github.com/testcontainers/testcontainers-python/issues/709 )

So I have added a basic example, feel free to change the docker image/port for something else

[Yourgene]

Hi, I had the same "issue" as you few days ago, and I had to look into code to find out that DockerContainer class is much rich than what is displayed in docs. Thanks for adding it!

If I had a suggestion, I'd also add the volume mapping example, just for the sake of it. Volume mapping is a basic use case too, as the ones you provided. If needed, here's the line you could add:

.with_volume_mapping('/path/to/host/dir/', "path/to/container/dir")

[Tranquility2]

Looks like this needs some more work

[vemonet]

@Tranquility2 it's litterally 10 lines in a readme of the most basic example of how most people will use this lib

Should not be too hard to get right no?

Note the one I wrote was almost a year ago, so the lib might have evolved since then