patch 8.2.2546: typo in mouse key name

Problem:    Typo in mouse key name.
Solution:   Fix the typo. (issue #4725)
diff --git a/src/version.c b/src/version.c
index dda530a..c63e60c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2546,
+/**/
     2545,
 /**/
     2544,