[BUG] Add foreman to docker config described in the README

[fbuys]

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Before we start...:

• I checked the documentation and found no answer
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Expected behavior:

Information about how to run dotenv_validator when you use foreman.

Actual behavior:

No informatino about how use dotenv_validator when you use foreman.

Context and environment:

We can update this part of the README: https://github.com/fastruby/dotenv_validator#if-you-use-docker-compose-read-this
to explain that it applies to foreman too.

For more context refer to this issue: fastruby/rails-template#23

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[aisayo]

@fbuys @arielj I realized there is a discussion on whether it is necessary to add this documentation to the README on issue #23, want to confirm if we still want to move forward with this?

[arielj]

@aisayo this foreman issue is unrelated to the dependency on the dotenv gem, we have to still explain in the readme that foreman (like docker), read the .env file differently than dotenv

[etagwerker]

@arielj The table in the README no longer points to a section of the README in the dotenv project. I assume that README's sections changed and maybe it should now point to: https://github.com/bkeepers/dotenv?tab=readme-ov-file#customizing-rails

[etagwerker]

I think it would be useful to add something to the README that points to this issue: ddollar/foreman#702 (comment)

There is a workaround for people who want to use both dotenv and foreman