patch 8.2.3858: Vim9: not enough tests

Problem:    Vim9: not enough tests.
Solution:   Add tests for :try/:catch and :redir. Add missing type check.
diff --git a/src/testdir/test_vim9_cmd.vim b/src/testdir/test_vim9_cmd.vim
index 6e01d99..2d86b6b 100644
--- a/src/testdir/test_vim9_cmd.vim
+++ b/src/testdir/test_vim9_cmd.vim
@@ -1558,6 +1558,23 @@
     redir END
   END
   CheckDefFailure(lines, 'E1141:')
+
+  lines =<< trim END
+      var text: string
+      redir => text
+        echo 'hello'
+        redir > Xfile
+      redir END
+  END
+  CheckDefFailure(lines, 'E1185:')
+
+  lines =<< trim END
+      var text: number
+      redir => text
+        echo 'hello'
+      redir END
+  END
+  CheckDefFailure(lines, 'E1012:')
 enddef
 
 def Test_echo_void()