Remove not existing paths from root composer.json.
For 8.7 the path to context_help must be kept.

Resolves: #82546
Releases: master, 8.7
Change-Id: Iea32a481011d906ea7057072413e6ae01a2ce771
Reviewed-on: https://review.typo3.org/54211


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Morton Jonuschat <m.jonuschat@mojocode.de>
Tested-by: Morton Jonuschat <m.jonuschat@mojocode.de>
Reviewed-by: Jan Stockfisch <jan.stockfisch@googlemail.com>
Reviewed-by: Frank Naegler <frank.naegler@typo3.org>
Tested-by: Frank Naegler <frank.naegler@typo3.org>