[INTERNAL][FIX] sap.m.BusyDialog: Add padding to footer

Add .sapMBusyDialogFooter class to the toolbar which
is rendered only for desktop.

Change-Id: If97cf12d03807a38d6e3a970ed8c34ae87addd78
Signed-off-by: Deyan Yanakiev <deyan.yanakiev@sap.com>
Merge "[INTERNAL][FIX] sap.m.BusyDialog: Add padding to footer"