wayland: 1.14.0 -> 1.15.0

Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools.

This update was made based on information from https://repology.org/metapackage/wayland/versions.

These checks were done:

- built on NixOS
- ran ‘/nix/store/ij8fn0all1sl84wy94wpvc0ih0c1bidq-wayland-1.15.0/bin/wayland-scanner -h’ got 0 exit code
- ran ‘/nix/store/ij8fn0all1sl84wy94wpvc0ih0c1bidq-wayland-1.15.0/bin/wayland-scanner --help’ got 0 exit code
- ran ‘/nix/store/ij8fn0all1sl84wy94wpvc0ih0c1bidq-wayland-1.15.0/bin/wayland-scanner help’ got 0 exit code
- ran ‘/nix/store/ij8fn0all1sl84wy94wpvc0ih0c1bidq-wayland-1.15.0/bin/wayland-scanner -v’ and found version 1.15.0
- ran ‘/nix/store/ij8fn0all1sl84wy94wpvc0ih0c1bidq-wayland-1.15.0/bin/wayland-scanner --version’ and found version 1.15.0
- found 1.15.0 with grep in /nix/store/ij8fn0all1sl84wy94wpvc0ih0c1bidq-wayland-1.15.0
- directory tree listing: https://gist.github.com/4f5bd9b49f975338e758858eb2b89e4d