fix(protocol-designer): fix logic for terminal step icon

This fixes a bug where the starting deck terminal step icon was being incorrectly determined as the end icon, because we were checking the title text of the step, which is subject to change. To fix this, we determine the icon based on step ID.

protocol-designer/src/pages/Designer/ProtocolSteps/Timeline/TerminalItemStep.tsx

@@ -83,7 +83,7 @@ export function TerminalItemStep(props: TerminalItemStepProps): JSX.Element {
       <StepContainer
         {...{
           stepId: `TerminalItem_${id}`,
-          iconName: title === 'Starting deck state' ? 'ot-start' : 'ot-end',
+          iconName: id === '__initial_setup__' ? 'ot-start' : 'ot-end',
           hovered,
           selected,
           title,