Ensure more explicit system ordering for preparing view target. (#15000)

Fixes #14993 (maybe). Adds a system ordering constraint that was missed
in the refactor in #14833. The theory here is that the single threaded
forces a topology that causes the prepare system to run before
`prepare_windows` in a way that causes issues. For whatever reason, this
appears to be unlikely when multi-threading is enabled.

crates/bevy_render/src/view/mod.rs

@@ -123,7 +123,8 @@ impl Plugin for ViewPlugin {
                 (
                     prepare_view_attachments
                         .in_set(RenderSet::ManageViews)
-                        .before(prepare_view_targets),
+                        .before(prepare_view_targets)
+                        .after(prepare_windows),
                     prepare_view_targets
                         .in_set(RenderSet::ManageViews)
                         .after(prepare_windows)