Terminal: Remove crashy assertion about line length

If we resize/maximize the window, we might end up with some lines in
history that had a different length than the current terminal width.
That's okay, so let's not crash because of it.

Fixes #620.

Applications/Terminal/TerminalWidget.cpp

@@ -240,7 +240,6 @@ void TerminalWidget::paint_event(GPaintEvent& event)
         // the character itself in the center of the columns
         // its bytes take up as far as the terminal is concerned.
 
-        ASSERT(line.text().length() == m_terminal.columns());
         Utf8View utf8_view { line.text() };
 
         for (auto it = utf8_view.begin(); it != utf8_view.end(); ++it) {