widget: Correct end row in calls to get_text()
widget: Correct end row in calls to get_text()

We need to pass row+1 if we use -1 as end column to mean
'all the text on the last row'.

saitoha/vte-sixel,thestinger/vte-ng,saitoha/vte-sixel,thestinger/vte-ng,saitoha/vte-sixel,thestinger/vte-ng