patch 8.2.1350: Vim9: no test for error message when redefining function

Problem:    Vim9: no test for error message when redefining function.
Solution:   Add a test.

src/testdir/test_vim9_script.vim

@@ -1651,6 +1651,19 @@ def Test_func_overrules_import_fails()
   delete('XexportedFunc.vim')
 enddef
 
+def Test_func_redefine_fails()
+  let lines =<< trim END
+    vim9script
+    def Func()
+      echo 'one'
+    enddef
+    def Func()
+      echo 'two'
+    enddef
+  END
+  CheckScriptFailure(lines, 'E1073:')
+enddef
+
 def Test_fixed_size_list()
   # will be allocated as one piece of memory, check that changes work
   let l = [1, 2, 3, 4]

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1350,
 /**/
     1349,
 /**/