docs: update EMULATOR.md

[kolea2]

Thank you for opening a Pull Request! Before submitting your PR, there are a few things you can do to make sure it goes smoothly:

• Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea.
• Follow the instructions in CONTRIBUTING. Most importantly, ensure the tests and linter pass by running bundle exec rake ci in the gem subdirectory.
• Update code documentation if necessary.

closes: #<issue_number_goes_here>