add function to automate badge update

[benvanwerkhoven]

List of related issues or pull requests

Refs: #ISSUE_NUMBER

Describe the changes made in this pull request

I've made a very small addition to howfairis to make it possible to automate updating the fair-software.eu badge inside a project's README. The goal is to use howfairis inside a GitHub action that checks the compliance and directly updates the badge instead of failing the workflow.

To this end, the command line option "-a" or "--auto" has been added. As well as one function automate_call_to_action that has been adapted from the print_call_to_action function. If you want I'm happy to rename the module from print_call_to_action.py to just call_to_action.py or something similar, since the module does more than just printing now.

I have added a test for automate_call_to_action to tests/test_cli.py.

I have also tested the automation of using "howfairis --auto" inside a GitHub action workflow. The test repository is here:
https://github.com/benvanwerkhoven/gh-actions-test-release
The workflow file that automatically updates the badge is here:
https://github.com/benvanwerkhoven/gh-actions-test-release/blob/main/.github/workflows/update-fair-software-badge.yml
You can see the "actions user" has updated the README automatically:
https://github.com/benvanwerkhoven/gh-actions-test-release/commits/main
To test this I also had to modify the howfairis-github-action. I can make a pull request for those additions later. I think it would be nice to support a user-specified option in that action to allow the user to enable this automation.

It would work even slightly better if howfairis could be run in a local git repository. Because even if your local files are different howfairis only checks what's on github. In reality, only the check "has_open_repository" really needs the GitHub URL and even that could be extracted from local files using 'git remote -v'. This point is not really related to the pull request, I'll create a separate issue to discuss this idea.

Instructions to review the pull request

# make a new temporary directory and cd into it
cd $(mktemp -d --tmpdir howfairis.XXXXXX)

# get a copy of the repo
git clone https://github.com/fair-software/howfairis .

# checkout the work from this branch 
git checkout <this branch>

# create a virtual environment named venv3
python3 -m venv venv3

# activate the virtual environment
source venv3/bin/activate

# update pip and friends
python3 -m pip install --upgrade pip wheel setuptools

# install runtime dependencies
python3 -m pip install .

# and, if you need it, the development tools
python3 -m pip install .[dev]

Keep what you need from below, extend as necessary

# run the unit tests
pytest

# tests against a live infrastructure
pytest livetests/

# cli tests
bash clitests/script.sh

# run linter
prospector

# import style
isort --check-only howfairis

# any additional steps for checking
# I have added a test for the code to tests/test_cli.py which is ran by pytest, but if you'd like to do a 'live' test you can do a pull request to change the README.rst with the wrong badge on this repo:
git clone [email protected]:benvanwerkhoven/gh-actions-test-release.git
And the GitHub action workflow will correct the badge automatically after the pull request has been merged.