patch 9.0.2051: Vim9: wrong error for non-existing object var

Problem:  Vim9: wrong error for non-existing object var
Solution: mention object or class depending on whether
          the var is an object or class variable.

closes: #13384
closes: #13387

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>
diff --git a/src/version.c b/src/version.c
index 2d437d8..87ed0b2 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2051,
+/**/
     2050,
 /**/
     2049,