patch 8.2.2184: Vim9: no error when using "2" for a line number

Problem:    Vim9: no error when using "2" for a line number.
Solution:   Give an error message if the line number is invalid. (closes #7492)
diff --git a/src/testdir/test_vim9_builtin.vim b/src/testdir/test_vim9_builtin.vim
index a050467..0f03d1f 100644
--- a/src/testdir/test_vim9_builtin.vim
+++ b/src/testdir/test_vim9_builtin.vim
@@ -185,6 +185,20 @@
   count('ABC ABC ABC', 'b', false)->assert_equal(0)
 enddef
 
+def Test_cursor()
+  new
+  setline(1, range(4))
+  cursor(2, 1)
+  assert_equal(2, getcurpos()[1])
+  cursor('$', 1)
+  assert_equal(4, getcurpos()[1])
+
+  var lines =<< trim END
+    cursor('2', 1)
+  END
+  CheckDefExecAndScriptFailure(lines, 'E475:')
+enddef
+
 def Test_executable()
   assert_false(executable(""))
   assert_false(executable(test_null_string()))