This adds the kernel append input. New arguments can be added by pressing the "Add" button or hitting Enter after the argument.
The kernel arguments linked to a selected OpenSCAP profile are rendered in a category marked as "Required by OpenSCAP" and are read only.
This updates `<ChippingInput>` component to resolve two bugs:
- validation wasn't triggered when using the plus button on Timezone and Locale steps
- error text wasn't reset when the value was changed or cleared
