fix: use prepare script in package.json to check for package manager
fix: use prepare script in package.json to check for package manager

fix #591

MartinHelmut/number-generator,MartinHelmut/number-generator,MartinHelmut/number-generator,MartinHelmut/number-generator,MartinHelmut/number-generator,MartinHelmut/number-generator