patch 8.2.4212: window title test still fails in some configurations

Problem:    Window title test still fails in some configurations.
Solution:   Explicitly set the 'title' option.
diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index edd03e3..917e89f 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -1637,6 +1637,7 @@
   endif
 
   let lines =<< trim END
+      set title
       edit Xa.txt
       let g:buf = bufadd('Xb.txt')
       inoremap <F2> <C-R>=setbufvar(g:buf, '&autoindent', 1) ?? ''<CR>
diff --git a/src/version.c b/src/version.c
index 18d8fc7..fab7939 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4212,
+/**/
     4211,
 /**/
     4210,