Fix html injection in Autofill confirmation dialog

AutofillService can inject html in its label. The label will
be padded with line breaks which puts the warning off screen.
To fix the issue, disable html injection of the label.

Bug: 216117246
Test: Manual, check the label of the sample in
      the confirmation dialog
Change-Id: I244d8e9eadbacae6af615d1d2a5a99c86e4fa456