Introduce a .dotenv.config file to store and read flags for Dotenv CLI

[FranzGB]

The current implementation of the Dotenv Command Line Interface (CLI) requires users to provide multiple flags in order to execute a program with specific environment variables. This can result in a lengthy and unwieldy command.

To address this issue, it is proposed that a .dotenv.config file be introduced. This file will contain the necessary flags to be passed to the CLI and will be read by Dotenv, allowing users to execute programs with the required environment variables in a more concise and streamlined manner.

This approach is inspired by the behavior of RSpec, a popular testing framework for Ruby. By introducing a .dotenv.config file, users will be able to more easily manage the necessary flags for their programs and streamline their workflow.

Example:

# .dotenv.config
-x .env.example
-x .env.example.db
-f .env.db 

[CristhianMotoche]

Hey @FranzGB I've assigned @flandrade to solve this issue. Could you please follow up with her on the development of this feature?