Unless the nurse is incontinent and needs to wear diapers for protection then no the nurses do not wear diapers.
The nurse will hold their pee in until they get a restroom break and they will use the restroom as soon as they can.
When the nurse is not busy they will usually go ahead and take a quick restroom break to go pee so that their bladder doesn't fill up.
My sister is a nurse and she doesn't wear diapers while working as a nurse or at any other time because she's not incontinent.
Nurses do get restroom breaks and it would be kind of unsanitary for the nurse to wear diapers and would be really inconvenient because the nurse would need to take time to change their diaper.