patch 8.2.4020: debugger test fails

Problem:    Debugger test fails.
Solution:   Fix import statement.
diff --git a/src/version.c b/src/version.c
index ddc986b..d3732cb 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4020,
+/**/
     4019,
 /**/
     4018,