[3.12] gh-115145: Update documentation about PyThreadState_DeleteCurrent (gh-124920) (gh-124931)

gh-115145: Update documentation about ``PyThreadState_DeleteCurrent`` (gh-124920)
(cherry picked from commit 9eeb21b)

Co-authored-by: Donghee Na <[email protected]>

Author: miss-islington

Doc/c-api/init.rst

@@ -1269,7 +1269,7 @@ All of the following functions must be called after :c:func:`Py_Initialize`.
 .. c:function:: void PyThreadState_DeleteCurrent(void)
 
    Destroy the current thread state and release the global interpreter lock.
-   Like :c:func:`PyThreadState_Delete`, the global interpreter lock need not
+   Like :c:func:`PyThreadState_Delete`, the global interpreter lock must
    be held. The thread state must have been reset with a previous call
    to :c:func:`PyThreadState_Clear`.