fix(generic): Migrate ServerContainer from deprecated decorator to HttpWaitStrategy (#971)

Hi there, I've seen this deprecation warning in a generic container.
This is my first PR in this project; I'm open to any feedback you may
have!

Related:
https://github.com/testcontainers/testcontainers-python/issues/874

Also updates the docs, highlighted in [this
comment](https://github.com/testcontainers/testcontainers-python/issues/874#issuecomment-3587724726)

Co-authored-by: Jon Miller <jonmiller@netflix.com>
Co-authored-by: Roy Moore <roy@moore.co.il>