Motivation for this change

This is a bugfix release for v4.18.

• Move parent nodes in scratchpad correctly
• i3bar: Call cont_child() more liberally
• Fix load_layout crash when floating node doesn't have CT_FLOATING_CON parent
• Fix SEGFAULT when i3bar receives invalid input
• Revert "floating_reposition: avoid extra tree_render"
• Call tree_render if floating move changes workspace
• Update EWMH properties on workspace move
• cmd_focus_sibling: Fix crash on workspace level

https://i3wm.org/downloads/RELEASE-NOTES-4.18.1.txt

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

@modulistic @fpletz @globin