modelfile: added gl.inet MT3000 (Beryl)

[armari4n]

No description provided.

[Noki]

you can do the changes to the file, and then use the following to update your existing commit:

git add group_vars/model_glinet_gl_mt3000.yml
git commit --amend
git push --force

[FFHener]

Please do a interactive rebase to get rid of these work in progress commits

git rebase -i origin/main

and then push again with force