patch 8.2.0286: cannot use popup_close() for a terminal popup

Problem:    Cannot use popup_close() for a terminal popup.
Solution:   Allow using popup_close(). (closes #5666)
diff --git a/src/popupwin.c b/src/popupwin.c
index 56d04b5..4078378 100644
--- a/src/popupwin.c
+++ b/src/popupwin.c
@@ -2360,7 +2360,12 @@
     int		id = (int)tv_get_number(argvars);
     win_T	*wp;
 
-    if (ERROR_IF_ANY_POPUP_WINDOW)
+    if (
+# ifdef FEAT_TERMINAL
+	// if the popup contains a terminal it will become hidden
+	curbuf->b_term == NULL &&
+# endif
+	    ERROR_IF_ANY_POPUP_WINDOW)
 	return;
 
     wp = find_popup_win(id);