Add websocket-jetty11 permissions for prototyping

[basil]

Description

Like #2638, but for Jetty 11. Even though we're not using Jetty 11 yet, the lack of these permissions prevents me from getting an incremental build of jenkinsci/jenkins#6085:

Invalid archive retrieved from Jenkins, perhaps the plugin is not properly incrementalized?
Error: ZIP error: Error: No permissions for org/jenkins-ci/main/websocket-jetty11/2.363-rc32712.2307a_6dc9273/websocket-jetty11-2.363-rc32712.2307a_6dc9273-sources.jar from https://ci.jenkins.io/job/Core/job/jenkins/job/PR-6085/3/artifact/**/*2307a*6dc9273*/*2307a*6dc9273*/*zip*/archive.zip

The lack of that incremental build prevents me from bootstrapping the test harness and doing further prototyping, so I would like to get these permissions set up.

• https://github.com/jenkinsci/jenkins

Submitter checklist for adding or changing permissions

Always

• Add link to plugin/component Git repository in description above

For a newly hosted plugin only

• Add link to resolved HOSTING issue in description above

For a new permissions file only

• Make sure the file is created in permissions/ directory
• artifactId (pom.xml) is used for name (permissions YAML file).
• groupId / artifactId (pom.xml) are correctly represented in path (permissions YAML file)
• Check that the file is named plugin-${artifactId}.yml for plugins

When adding new uploaders (this includes newly created permissions files)

• Make sure to @mention an existing maintainer to confirm the permissions request, if applicable
• Use the Jenkins community (LDAP) account name in the YAML file, not the GitHub account name
• Make sure to @mention the users being added so their GitHub account names are known if they require GitHub merge access (see below).
• All newly added users have logged in to Artifactory at least once

Reviewer checklist (not for requesters!)

• Check this if newly added person also needs to be given merge permission to the GitHub repo (please @ the people/person with their GitHub username in this issue as well). If needed, it can be done using an IRC Bot command
• Check that the $pluginId Developers team has Admin permissions while granting the access.
• In the case of plugin adoption, ensure that the Jenkins Jira default assignee is either removed or changed to the new maintainer.
• If security contacts are changed (this includes add/remove), ping the security officer (currently @Wadeck) in this pull request. If an email contact is changed, wait for approval from the security officer.

There are IRC Bot commands for it

[basil]

Thank you very much!