patch 8.1.2374: unused parts of libvterm are included

Problem:    Unused parts of libvterm are included.
Solution:   Delete the unused files.
diff --git a/src/version.c b/src/version.c
index b0c3fc9..5b4b898 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2374,
+/**/
     2373,
 /**/
     2372,