Migrated CI pipeline from GitLab to GitHub Actions to allow forked repos to run test pipelines

[chrisBrookes93]

Problem It appears the GitLab pipeline fails to run on branches/pull requests from forked repos. I've checked the hook log and its failing with HTTP 400 {"message":{"base":["Pull requests from fork are not supported"]}}

It looks as though this is a general limitation with GitLab (see https://jira.hyperledger.org/browse/IS-1497). This PR moves the CI away from GitLab to instead use GitHub Actions. This feels a lot tidier and means that this repo no longer needs to be mirrored on GitLab.

Solution Test Pipeline is now executed through GitHub Actions, triggered by a push or a pull request. This comes in the form of a GH Action Workflow and removal of the GitLab pipeline yaml file. Some improvements have also been added, namely testing against Python3.9 as well as MacOS and Windows.

Implications

• There are no actual code changes and the (now enhanced) pipeline is all passing. I don't expect this to have any impact to the functional usage of the library
• There is a PR currently open which will have some light merge conflicts with these changes. This other PR should now be able to make use of the test pipeline.

Possible Future Work

• Setup a workflow to run daily that tests against the latest Windows/Linux/Mac and latest (stable) Python to highlight any future incompatibilities via email notification.
• Move from unittest to pytest for running unit tests, and also report unit test coverage as part of the pipeline.
• Create workflow to publish to PyPi (when merging into master).
• A general review of project metadata files and whether we should move to using pyproject.toml.

[adiroiban]

This is how the main branch status looks in GitHub GUI and why I want short names for a workflow

[adiroiban]

Looks good. Thanks.

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It's ok to have the HTML log as artifact. You know best how to use the tool :p

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It looks like your local $ git config user.email is configured with an email not register in GitHub, so GitHub things that the code was contributed by 2 different persons. This is why the merge on this PR looks like done by Chris and Chris :)