patch 8.1.0374: moving the cursor is slow when 'relativenumber' is set

Problem:    Moving the cursor is slow when 'relativenumber' is set.
Solution:   Only redraw the number column, not all lines.
diff --git a/src/version.c b/src/version.c
index a4df820..ca6ac59 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    374,
+/**/
     373,
 /**/
     372,