Notifications don't work in react strict mode

[unique shale]

Starting with 5.1.3 notifications no longer work in strict mode https://codesandbox.io/s/elegant-glitter-82vvlv?file=/src/index.tsx
If compatibility is to be broken, we should include a note in the documentation, similar to RTE https://mantine.dev/others/rte/#react-strict-mode-limitations

[honest patio]

Seems this is related to the latest discussion in #972850721244471436