Problem/Feature

For the DropList used for the Tags menu in the convo redesign, we want to alter the elements displayed based on whether the search input has a value (Jira). This PR adds an onInputChange callback to allow for that as recommended by @tinkertrain here

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Guidelines

Make sure the pull request:

[x] Follows the established folder/file structure
[x] Adds unit tests
[ ] If it is a refactor or change to an existing component, have you verified it won't break existing Cypress tests or have you updated them?
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helpscout / hsds-react

HSAPPUI-310: Add onInputChange callback to DropList #998

Problem/Feature

Guidelines