patch 8.2.4670: memory allocation failures for new tab page not tested

Problem:    Memory allocation failures for new tab page not tested.
Solution:   Add tests with failing memory allocation. (Yegappan Lakshmanan,
            closes #10067)
diff --git a/src/version.c b/src/version.c
index 92198be..487a134 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4670,
+/**/
     4669,
 /**/
     4668,