Log Message:
ibus, ibus-python: update to 1.5.18.

pkgsrc changes:
- explicitly specify USE_TOOLS+=gmsgfmt to handle msgfmt --desktop
- pull an upstream change to fix a configure bug in 1.5.18
- use a new unicode character database

Upstream changes (from https://github.com/ibus/ibus/releases):

1.5.18

* tools: Do not change keymaps with 'use-system-keyboard-layout' c360818
* src: Fix GVariant leaks (Carlos Garnacho) 1cbe867
* src: Added some error handlings from a code review f5e0752
* src: Add libgobject.so to LDADD for Debian libtool (Danny) a28fa74
* src: Reintroduce the hex mode keybind with an environment variable
  (Aaron Muir Hamilton) 88b9a93
* ui/gtk3: Translate input method name in ibus (Peng Wu) 0ab0dd3
* Added DBus filtering against malware bfe57d2
* Implement Unicode choice on Emojier e17c998 4cfd5ad d1ebb3d fc54b0c afe60c1
* Implement ibus-extension-gtk3 for the global keybinding fb07f64 c57b7c3
* Disable panel extension for 'gdm' and 'liveuser' user 7ccbd21 ece320b
* ui/gtk3: Set title string in gnome-shell 56c67b1
* Add ISSUE_TEMPLATE ff611a4 9f2699c
* Updated translations 366963d 73b420f