Correctly recognize `typing_extensions.NewType` #11353

Job	Run time
Test mypyc suite with 32-bit Python	10m 57s
Test suite with py38-ubuntu, mypyc-compiled	29m 36s
Test suite with py38-windows-64	39m 23s
Test suite with py39-ubuntu	24m 20s
Test suite with py310-ubuntu	23m 25s
Test suite with py311-ubuntu, mypyc-compiled	24m 2s
Test suite with py312-ubuntu, mypyc-compiled	28m 49s
mypyc runtime tests with py38-macos	9m 59s
mypyc runtime tests with py38-debug-build-ubuntu	7m 4s
Type check our own code (py38-ubuntu)	2m 49s
Type check our own code (py38-windows-64)	3m 59s
Formatting and code style with Black + ruff	51s
	3h 25m 14s

Provide feedback