patch 8.2.0292: Vim9: CHECKNR and CHECKTYPE instructions not tested

Problem:    Vim9: CHECKNR and CHECKTYPE instructions not tested.
Solution:   Add tests.
diff --git a/src/testdir/test_vim9_expr.vim b/src/testdir/test_vim9_expr.vim
index fabbd9b..312d633 100644
--- a/src/testdir/test_vim9_expr.vim
+++ b/src/testdir/test_vim9_expr.vim
@@ -781,6 +781,11 @@
 
   call CheckDefExecFailure("echo s:doesnt_exist", 'E121:')
   call CheckDefExecFailure("echo g:doesnt_exist", 'E121:')
+
+  call CheckDefExecFailure("let x = +g:astring", 'E1030:')
+  call CheckDefExecFailure("let x = +g:ablob", 'E974:')
+  call CheckDefExecFailure("let x = +g:alist", 'E745:')
+  call CheckDefExecFailure("let x = +g:adict", 'E728:')
 endfunc
 
 let g:Funcrefs = [function('add')]