Documentation/git-sparse-checkout.txt: fix a typo

This typo was introduced in 94c0956b60 (sparse-checkout: create builtin
with 'list' subcommand, 2019-11-21).

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/git-sparse-checkout.txt b/Documentation/git-sparse-checkout.txt
index 9c3c66c..a3c920f 100644
--- a/Documentation/git-sparse-checkout.txt
+++ b/Documentation/git-sparse-checkout.txt
@@ -5,7 +5,7 @@
 ----
 git-sparse-checkout - Initialize and modify the sparse-checkout
 configuration, which reduces the checkout to a set of paths
-given by a list of atterns.
+given by a list of patterns.
 
 
 SYNOPSIS