Custom Applications v21.3

The Application Kit packages have been released with a minor version v21.3.

This release includes several new features that we would like to present:

• New CLI commands login and config:sync to help maintaining Custom Applications.
• New layout UI components <TabularMainPage> and <TabularDetailPage>. In addition to that, a new <TabHeader> component is exported from the @commercetools-frontend/application-components package to be used in the tabular UI components <TabularModalPage>, <TabularMainPage> and <TabularDetailPage>.
• New ESLint config @commercetools-backend/eslint-config-node for Node.js projects with built-in TypeScript support.
• The notification components now support the aria role alertdialog and the aria-describedby attributes. This helps in particular to write more specific and relevant selector in tests.