[3.13] Fix grammar typo in `Doc/c-api/arg.rst` (GH-130741) (#130759)

Fix grammar typo in `Doc/c-api/arg.rst` (GH-130741)
(cherry picked from commit 37145cb89fe806377a5e9ed1fdac92dd3a5df2c0)

Co-authored-by: Arijit Kumar Das <arijitkrdas2004@outlook.com>

diff --git a/Doc/c-api/arg.rst b/Doc/c-api/arg.rst
index 209056ef2f8bce30fb00c76dce2fbcac7df4fcf1..15402a4c48f56994aa126c06b2107ec6fb30844e 100644 (file)
--- a/Doc/c-api/arg.rst
+++ b/Doc/c-api/arg.rst
@@ -5,7 +5,7 @@
 Parsing arguments and building values
 =====================================
 
-These functions are useful when creating your own extensions functions and
+These functions are useful when creating your own extension functions and
 methods.  Additional information and examples are available in
 :ref:`extending-index`.