Change composer call for testing stage

3 jobs for clean-composer-json in 2 minutes and 3 seconds (queued for 1 second)
Status Job ID Name Coverage
failed test #8527


skipped build #8528
skipped layout #8529
Name Stage Failure
test Test There is an unknown failure, please try again
Generating  class alias map file
Inserting class alias loader into main autoload.php file
$ mkdir $TYPO3_PATH_WEB/fileadmin/ && touch $TYPO3_PATH_WEB/fileadmin/currentcoredata.json
$ ./composer.phar test:unit
Do not run Composer as root/super user! See for details
> [ -e bin/phpunit ] || composer install
sh: composer: not found
Script [ -e bin/phpunit ] || composer install handling the test:unit event returned with error code 127
ERROR: Job failed: exit code 127