Add a page about bulk application deployment

docs/use-cases/virtual-lab/bulk-application-deployment.md

...-cases/virtual-lab/img/bulk-app-deployment-app-status.png

...use-cases/virtual-lab/img/bulk-app-deployment-details.png

...se-cases/virtual-lab/img/bulk-app-deployment-homepage.png

.../use-cases/virtual-lab/img/bulk-app-deployment-step01.png

.../use-cases/virtual-lab/img/bulk-app-deployment-step02.png

.../use-cases/virtual-lab/img/bulk-app-deployment-step03.png

mkdocs.yml