TRUNK-6058: Create CI Process to create liquibase snapshots

[IamMujuziMoses]

Issue I worked on

see https://issues.openmrs.org/browse/TRUNK-6058

Checklist: I completed these to help reviewers :)

• [x] My IDE is configured to follow the code style of this project.

  No? Unsure? -> configure your IDE, format the code and add the changes with git add . && git commit --amend

• [x] I have added tests to cover my changes. (If you refactored existing code that was well tested you do not have to add tests)

  No? -> write tests and add them to this commit git add . && git commit --amend

• [x] I ran mvn clean package right before creating this pull request and added all formatting changes to my commit.

  No? -> execute above command

• [x] All new and existing tests passed.

  No? -> figure out why and add the fix to your commit. It is your responsibility to make sure your code works.

• [x] My pull request is based on the latest changes of the master branch.

  No? Unsure? -> execute command git pull --rebase upstream master

[IamMujuziMoses]

@dkayiwa @ibacher could you please review this PR, your feedback will be appreciated.

[ibacher]

The idea of the ticket is just to automate the process described here. I can't imagine that we can merge this as-is without breaking things, since you've now turned the api JAR (which we use everywhere) into a shaded JAR.