src: Save address file in XDG_RUNTIME_DIR
src: Save address file in XDG_RUNTIME_DIR

Currently the address file is saved in XDG_CONFIG_DIR, however since it
is not a config or preferences file perhaps it should instead be saved
to XDG_RUNTIME_DIR.

BUG=https://github.com/ibus/ibus/pull/2128

fujiwarat/ibus,fujiwarat/ibus,fujiwarat/ibus,ibus/ibus,fujiwarat/ibus,ibus/ibus,ibus/ibus,ibus/ibus