gui/main: Add close buttons to all message boxes
gui/main: Add close buttons to all message boxes

  We use message boxes to display some errors but those don't have close
  buttons so users can't close them.

  We can use user choices buttons to offer a close option.

cozy-labs/cozy-desktop,cozy-labs/cozy-desktop,cozy-labs/cozy-desktop,cozy-labs/cozy-desktop