Use typing_extensions to support versions [3.8, 3.11[

Author: dylan-robins

src/poetry/core/packages/project_package.py

@@ -5,10 +5,11 @@
 from typing import TYPE_CHECKING
 from typing import Literal
 from typing import Mapping
-from typing import NotRequired
 from typing import Sequence
 from typing import TypedDict
 
+from typing_extensions import NotRequired
+
 from poetry.core.constraints.version import parse_constraint
 from poetry.core.version.markers import parse_marker