patch 8.2.4864: Vim9: script test fails

Problem:    Vim9: script test fails.
Solution:   Remove "if" around declaration.

src/testdir/test_vim9_script.vim

@@ -4132,10 +4132,8 @@ def Test_echo_uninit_variables()
   var Var_func: func
   var var_string: string
   var var_blob: blob
-  if has('job')
   var var_job: job
   var var_channel: channel
-  endif
   var var_list: list<any>
   var var_dict: dict<any>
 

src/version.c

@@ -746,6 +746,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4864,
 /**/
     4863,
 /**/