[Standardize the Pay Button] Expenses

[grgia]

Design Doc Section

⚠️ MERGE HOLD ON BE ⚠️

This section is dependent on:

NVP changes:
#55873 (FE Migration)
https://github.com/Expensify/Expensify/issues/465082 (BE Migration)
https://github.com/Expensify/Expensify/issues/465077 (Setting the NVP)

Goal

Update all pay buttons related to Expenses

[melvin-bot]

@hungvu193, @grgia, @getusha Eep! 4 days overdue now. Issues have feelings too...

[grgia]

Not overdue

[grgia]

Not overdue