TtContentRelation updatescript doesn't migrate all mm relations from news to tt_content

[patrickroquin]

Reproducing this issue

• Use content element relation
• Add a new news record with content element relation in TYPO3 6.2 with news version 3.1.0
• Make a copy of this news record (the content element id will be the same!!! this is different in TYPO3 7.6 with news 4.2.1)
• Migratie it to TYPO3 7.6 with news version 4.2.1 and use the update script in the install tool (with news 3.2.0 changes relation from mm table to tx_news_related_news field in tt_content)

There will be some relations lost from news records to content elements, so some content elements will not be shown

Fix
Extend the update script TtContentRelation.php > performUpdate:
If there are more relations to the same content element, copy this content element

[georgringer]

Even though that the bug report is valid, I won't do any changes there anymore as I will remove the wizard with the next version.