TRUNK-6149: Add 'discontinue_reason' and 'discontinue_reason_non_coded' to Order object

[IamMujuziMoses]

Issue I worked on

see https://issues.openmrs.org/browse/TRUNK-6149

Checklist: I completed these to help reviewers :)

• 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

• 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

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

  No? -> execute above command

• 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.

• 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 @mogoodrich could you please review this PR

[github-actions]

tl;dr our action detected no activity on this PR and will close it in 30 days if the stale label is not removed.

OpenMRS welcomes your contribution! It means a lot to us that you want to contribute to equity in healthcare!

This PR has not seen any activity in the last 5 months. That is why we wanted to check whether you are still working on it or need assistance from our side.
Please note that this is an automated message and we might very well be the reason why there has not been any activity lately. We certainly do not want to discourage you from contributing. We do need to be honest in that OpenMRS has limited resources for reviewing PRs.

If you do not have time to continue the work or have moved on you don’t need to do anything. We will automatically close the PR in 30 days. We hope to see you back soon :)
If you would like to continue working on it or require help from us please remove the stale label and respond by commenting on the issue.