ci: build docker image and healthcheck

[nawramm]

Finally got to sit down for a bit and work on this ~~There is a slight overlap between this and #623 which may make this PR unnecessary~~

Closes: #534

License Agreement for Contributions

By submitting this pull request, I acknowledge and agree that my contributions will be included in Stirling-PDF and that they can be relicensed in the future under MPL 2.0 (Mozilla Public License Version 2.0) license.

(This does not change the general open-source nature of Stirling-PDF, simply moving from one license to another license)

[Frooodle]

I was just wondering what happened to you doing this i assumed you dropped it and so i was doing something similar for my local testing planning to eventually migrate it https://github.com/Stirling-Tools/Stirling-PDF/blob/changes/test.sh

[Frooodle]

oh i see you noticed that PR

[Frooodle]

Having a dedicated github action for it however is still good, will test and merge this, thanks for the work!

[Frooodle]

Was testing using the local testing script i made to try avoid duplication

https://github.com/Stirling-Tools/Stirling-PDF/blob/githubActionTest/.github/workflows/test.yml

[nawramm]

Looks good to me, closing this PR.

I would suggest changing the versionNumber step to:

- name: Get version number
      id: versionNumber
      run: echo "name=versionNumber::$(./gradlew printVersion --quiet | tail -1)" >> "$GITHUB_ENV"

Then you can replace ${{ steps.versionNumber.outputs.versionNumber }} with $versionNumber

I think the docker-compose install step is redundant as the action for f3742eb ran succesfully