- Update wayland-protocols.keyring: Use gpg key by Daniel Stone to
verify sources.

- Update to version 1.33:
* xdg-shell: Clarify what a toplevel by default includes
* linux-dmabuf: sync changes from unstable to stable
* linux-dmabuf: require all planes to use the same modifier
* presentation-time: stop referring to Linux/glibc
* security-context-v1: Make sandbox engine names use reverse-DNS
* xdg-decoration: remove ambiguous wording in configure event
* xdg-decoration: fix configure event summary
* linux-dmabuf: mark as stable
* linux-dmabuf: add note about implicit sync
* security-context-v1: Document what can be done with the open
sockets
* security-context-v1: Document out of band metadata for flatpak