[BUGFIX] Fix PHP 8 strict warning in Package MetaData

A "type" does not need to be set in a composer.json,
so the checks for package type must account for the type
being null, to not trigger a warning in PHP 8

Releases: 11.5, main
Resolves: #96372
Change-Id: Ic607c3dbb16dfcf4a28b0417b8340be36bcafa87
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/72695


Tested-by: Markus Klein <markus.klein@typo3.org>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Simon Gilli <typo3@gilbertsoft.org>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Helmut Hummel <typo3@helhum.io>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Reviewed-by: Simon Gilli <typo3@gilbertsoft.org>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Helmut Hummel <typo3@helhum.io>