patch 8.2.2046: some test failures don't give a clear error

Problem:    Some test failures don't give a clear error.
Solution:   Use assert_match() and assert_fails() instead of assert_true().
            (Ken Takata, closes #7368)
diff --git a/src/version.c b/src/version.c
index ef0e157..f7c1f45 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2046,
+/**/
     2045,
 /**/
     2044,