patch 8.2.1755: Vim9: crash when using invalid heredoc marker

Problem:    Vim9: crash when using invalid heredoc marker. (Dhiraj Mishra)
Solution:   Check for NULL list. (closes #7027)  Fix comment character.
diff --git a/src/version.c b/src/version.c
index 1ee6801..2072b35 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1755,
+/**/
     1754,
 /**/
     1753,