[doc] Fix typo in idle.rst (GH-27903)


intially -> initially
(cherry picked from commit 0e8695ece0d3569eeb1b89c91a1b0aa3d34f228e)

Co-authored-by: Ikko Ashimine <eltociear@gmail.com>
diff --git a/Doc/library/idle.rst b/Doc/library/idle.rst
index 91c5405..d740973 100644
--- a/Doc/library/idle.rst
+++ b/Doc/library/idle.rst
@@ -518,7 +518,7 @@
 after adding imports at the top of a file.  This also increases
 possible attribute completions.
 
-Completion boxes intially exclude names beginning with '_' or, for
+Completion boxes initially exclude names beginning with '_' or, for
 modules, not included in '__all__'.  The hidden names can be accessed
 by typing '_' after '.', either before or after the box is opened.