Linting EVEREST configuration files on changes or overnight

[roliveira]

The EVEREST configuration cases can be linted whenever there is a commit, a pull request or overnight using GHA. This is a faster and less computationally intensive way to flag for errors in the config.

Initial proposal with GHA:

- name: lint everest configs
  run: |
    git clone https://github.com/equinor/everest-tutorials.git
    TUTORIAL_PATH=$(pwd)/everest-tutorials/data/drogon

    echo "Linting $TUTORIAL_PATH/well_rate/everest/model/drogon_wellrate.yml"
    config=$TUTORIAL_PATH/well_rate/everest/model/drogon_wellrate.yml
    sed -i '/^  simulation_folder:/d' $config
    everest lint $config