Changing the basic authentication credentials of a JIRA server isn't taken into account until restart

Steps to reproduce

1. In the JIRA administration, define a server with Basic authentication and save.
2. Use it in a jira macro.
3. In the JIRA administration, change only the username or password of that server and save.
4. Display the macro again.

Expected

The macro uses the new credentials.

Actual

The old credentials are still sent to JIRA. They are only replaced after a restart, or after a field of the server itself (id, URL, authentication type) is changed.

Reproduced with JIRA Macro 11.1.8 on XWiki 17.10.14.