Update governments.yml - Mexico SAT

[opensatmx]

Add Mexico/satmx, for Servicio de Administración Tributaria (SAT)

Thanks for the contribution! Below is a template that can make it easier when submitting your Organization:

Your Organization: Servicio de Administración Tributaria (SAT)
GitHub Organization url: @satmx
Country/Locality: Mexico City, Mexico

Inclusion requirements:

• Referenced account is an Organization not a User^
• If this is a government project, your Organization's description should include a reference to your country/agency.
• Make sure your Organization includes at least one public repository
• Please also include a URL for your organization that links back to your organization or agency homepage.

^ If you want to convert your account to an org, details can be found here: https://help.github.com/articles/converting-a-user-into-an-organization/

❤️ GitHub Government Contributors

[mcantu]

@opensatmx

• Hi, could you please confirm that you have a public repository published? per the requirements.
• Hola, ¿podría confirmar que tiene un repositorio público publicado? según los requisitos.

Thank you / gracias!

[mcantu]

Hola @opensatmx

• Aqui es como puedes crear un repo publico, como los requisitos lo piden.
• This is how you create an public repo within an organization, per the requirements.

https://docs.github.com/en/get-started/quickstart/create-a-repo

👀 @manuelbriseno @oscarmuller