Add GH template to all kytos-ng repos

[Vinicius Arcanjo]

To minimize trivial back and forth regarding PR description contents, let's add this template for all Kytos-ng repos

[David Ramirez]

We can add in the templates through adding .github repo to our organization. At least thats what I understand we can do according to this https://docs.github.com/en/communities/setting-up-your-project-for-healthy-contributions/creating-a-default-community-health-file