patch 8.2.3284: no error for insert() or remove() changing a locked blob

Problem:    No error for insert() or remove() changing a locked blob.
Solution:   Check a blob is not locked before changing it. (Sean Dewar,
            closes #8696)
diff --git a/src/testdir/test_eval_stuff.vim b/src/testdir/test_eval_stuff.vim
index 1fbb74b..ac9589d 100644
--- a/src/testdir/test_eval_stuff.vim
+++ b/src/testdir/test_eval_stuff.vim
@@ -65,9 +65,9 @@
 endfunc
 
 func Test_for_invalid()
-  call assert_fails("for x in 99", 'E714:')
-  call assert_fails("for x in function('winnr')", 'E714:')
-  call assert_fails("for x in {'a': 9}", 'E714:')
+  call assert_fails("for x in 99", 'E1098:')
+  call assert_fails("for x in function('winnr')", 'E1098:')
+  call assert_fails("for x in {'a': 9}", 'E1098:')
 
   if 0
     /1/5/2/s/\n