patch 8.1.1536: popup select test still fails on Mac

Problem:    Popup select test still fails on Mac.
Solution:   Set 'clipboard' to "autoselect"

src/testdir/test_popupwin.vim

@@ -328,6 +328,7 @@ func Test_popup_select()
   endif
   " create a popup with some text to be selected
   let lines =<< trim END
+    set clipboard=autoselect
     call setline(1, range(1, 20))
     let winid = popup_create(['the word', 'some more', 'several words here'], {
 	  \ 'drag': 1,

src/version.c

@@ -777,6 +777,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1536,
 /**/
     1535,
 /**/