Bug: Running Container with_network makes get_exposed_port unreliable

Describe the bug

Hello!

I have a case where I want to run several containers inside a specific docker network environment.
However when attaching a container to a network it seems that port forwarding is not attached to the new network - making the overall experience unstable(not able to get postgres URL, few containers like Minio do healthcheck that hangs etc)

It seems like this is not always the case however. Roughly 30% of the times the ports are actually forwarded and it succeeded. However most of the time it fails: resulting in hanging operations etc.

To Reproduce

Given a case as below. Keep in mind that sometimes it does work. Most of the time it won't.
Result will be that get_exposed_port operation hangs

from testcontainers.postgres import PostgresContainer
from testcontainers.core.network import Network

with Network() as network:
    c = PostgresContainer("postgres:13.3-alpine")
    c.with_network(network)
    c.start()
    print("Port: ", c.get_exposed_port(5432))
    c.stop()

Runtime environment

Provide a summary of your runtime environment. Which operating system, python version, and docker version are you using? What is the version of testcontainers-python you are using? You can run the following commands to get the relevant information.

# Get the operating system information (on a unix os).
$ uname -a
Darwin Henriks-MBP-2.fritz.box 23.5.0 Darwin Kernel Version 23.5.0: Wed May  1 20:16:51 PDT 2024; root:xnu-10063.121.3~5/RELEASE_ARM64_T8103 arm64
# Get the python version.
$ python --version
Python 3.12.3
# Get the docker version and other docker information.
$ docker info
Client:
 Version:           26.1.4
 API version:       1.45
 Go version:        go1.21.11
 Git commit:        5650f9b
 Built:             Wed Jun  5 11:26:02 2024
 OS/Arch:           darwin/arm64
 Context:           default

Server: Docker Desktop 4.31.0 (153195)
 Engine:
  Version:          26.1.4
  API version:      1.45 (minimum version 1.24)
  Go version:       go1.21.11
  Git commit:       de5c9cf
  Built:            Wed Jun  5 11:29:12 2024
  OS/Arch:          linux/arm64
  Experimental:     true
 containerd:
  Version:          1.6.33
  GitCommit:        d2d58213f83a351ca8f528a95fbd145f5654e957
 runc:
  Version:          1.1.12
  GitCommit:        v1.1.12-0-g51d5e94
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0
# Get all python packages.
$ pip freeze
docker==7.1.0
testcontainers==4.6.0

从 with_network、start 和 get_exposed_port 入口点开始，并复现提供的 PostgresContainer 示例。跟踪 Docker 网络连接和端口映射的处理方式，然后验证重复运行是否始终返回暴露的端口且不会挂起。