🐛 Join Program has `Unknown Error`

[lindaxiang]

Describe the bug

Program WCCPMP-US reports that some of their submitters encounter Unknown Error when join the program.

1. We have tested the issue in Prod:

• If we invite the person using OICR emails, there's no issue
• If we invite the person using Gmail, we can reproduce the Unknown Error issue

2. We also tested the issue in QA, and we could NOT reproduce the Unknown Error issue.

Steps To Reproduce

Steps to reproduce the behaviour:

1. Go to 'https://platform.icgc-argo.org/'
2. Login the Program Services with admin role
3. Click on test programs TEST-INTL or TEST-CA
4. Click Manage Program
5. Click ADD USERS
6. Input your name and gmail, select a role, and click ADD USERS
7. Go to your gmail inbox, and find the email
8. Click JOIN THE PROGRAM
9. See error
   

Expected behaviour

The submitter should be able to see the following interface to join the program

[joneubank]

The cause of this is that the Program Service endpoint used to confirm the invite information is currently set to require authorization. We need this endpoint to work for users that are not logged in (obviously).

The specific endpoint is GET /programs/joinProgramInvite. This can be moved to the PublicProgramController and the authorization annotation removed.

Endpoint code: https://github.com/icgc-argo/program-service/blob/develop/src/main/java/org/icgc/argo/program_service/controller/ProgramController.java#L230