Allow cleaning group pages names when migrating confluence rights

[mouhb]

Some context :

Currently users that are migrating large confluence instances with lots of users and groups are also doing a batch import of their users/group on XWiki before the running the migration. The LDAP User Import Application is for example used to import all groups and users available on an LDAP directory and to fill the groups with the corresponding users.
When a group is imported using the "LDAP User Import" Application (which is using the XWiki LDAP Authenticator API) the name of the group page created on XWiki is always cleaned, meaning that spaces, dots ('.'), and slashes (/) are removed from the original group name found in LDAP side. See : https://github.com/xwikisas/application-ldapuserimport/blob/main/application-ldapuserimport-api/src/main/java/com/xwiki/ldapuserimport/internal/job/DefaultLDAPGroupImportJob.java#L122. The method org.xwiki.contrib.ldap.XWikiLDAPUtils.java#cleanXWikiUserPageName(String pageName) is used to clean the group names. Also, note that all group names generated by the LDAP Authenticator API by default ends by the word "Group" which is an XWiki best practice for groups pages. So, for example we have the group name "Company All" in LDAP side the group "CompanyAllGroup" will be generated in XWiki side.

The issue with the Confluence Migrator is that when the rights are imported the group names set on the rights objects are kept as they are found on the confluence package except if a group mapping is provided. So, it would be nice if we have an option in the Confluence Migrator that forces cleaning and adding the word 'Group' on group names set during the rights migration.

[raphj]

Fixed at https://jira.xwiki.org/browse/CONFLUENCE-205.

[raphj]

See also #80