LDAP or Database picker doesn't work when the project or issue types are filter in the Context

High-level summary:

Database Picker and LDAP Picker scripted fields will not work in common scenarios, such as when the end user is a Jira Service Desk user that lacks the Browse Project permission for all projects in the instance.

Scenario 1

The problem is reproducible when login with a normal JIRA user and access from the standard JIRA issue screen

Steps to reproduce it

1. Follow the steps in https://scriptrunner.adaptavist.com/latest/jira/script-fields/database-picker.html to select projects from list.
2. Configure context to Bug issue type and global projects.
   
3. We will get this behaviour:
   

Workaround for scenario 1

Configure Context to the selected projects instead of using global.

Scenario 2

The problem is reproducible when login with non-licensed user and access from the JIRA service desk portal (get 403 error).

Steps to reproduce it:

1. Create a new LDAP or DB resources
2. Create a new Database or LDAP picker field and change the context to only Service Desk project and all issue types.
3. Login as a non-licensed user and go to the portal to create issue.
4. The Database or LDAP picker field shows empty value and get 403 error:
   

Workaround for scenario 2

Configure Context to all projects and all issue types.

Scenario 3

As scenario 4, but the logged in user does not have the Browse Project permission on any project in the Jira instance. Regardless of the field's configuration scheme (global or not) the user will be able to see, but not use database & LDAP picker fields that are on a customer support portal.

Workaround

Grant the Browse Project permission on some project in the instance (even a dummy project) to the Group *Anyone* to allow anonymous access. Verify that the project has a field configuration scheme associated with your script field (or that your script field is using the global configuration scheme).