Set up end-to-end / integration testing via GitHub actions

[oneillkza]

We should set up automated testing by running the complete workflow on a mini-example (including adding some small example data to the repo).

[Glenn032787]

I included a small test file in github_action branch which is generated from chr22 ASE simulated data and also randomly generated CNV and DMR data. I also included the github action yaml file which runs the workflow, however, github actions prevents it from using the --use-singularity command with snakemake when using premade snakemake github action (mentioned in this issue). I will try to either manually install snakemake into github runner or run unit tests.

[oneillkza]

Great!

And yeah, manually installing, either directly through apt, or via conda as per this comment, will be the way to go for running snakemake.

When I've run Travis in the past for this kind of testing, it allowed me to just run a few install commands before the test itself.

[Glenn032787]

Finally got github actions to run through with no issues! I have created a pull request #3 for adding the small example and adding github actions workflow to the repository. If there is no issues I will merge it to main.