Fix: typing_extensions import causing issues (#188)

* Bugfix for corrections handling

* Move typing_extensions import to TYPE_CHECKING block

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

pymatgen/analysis/defects/core.py

@@ -15,14 +15,14 @@
 from pymatgen.core import Element, PeriodicSite, Species
 from pymatgen.core.periodic_table import DummySpecies
 from pymatgen.symmetry.analyzer import SpacegroupAnalyzer
-from typing_extensions import Self
 
 from .utils import get_plane_spacing
 
 if TYPE_CHECKING:
     from numpy.typing import ArrayLike
     from pymatgen.core import Structure
     from pymatgen.symmetry.structure import SymmetrizedStructure
+    from typing_extensions import Self
 
 # TODO Possible redesign idea: ``DefectSite`` class defined with a defect object.
 # This makes some of the accounting logic a bit harder since we will probably