main/glib: upgrade to 2.78.0, main/gobject-introspection: upgrade to 1.78.0

Changelog glib:
Overview of changes in GLib 2.78.0, 2023-09-08


Bugs fixed:


#3095 Error handling of invalid GKeyFile string escape sequences changed in
GLib 2.77.3 (Philip Withnall)

!3559 gdb: Workaround optimized out quark_seq_id

!3561 meson: fix gnetworking.h install tag

!3562 gthread: Annotate g_thread_exit() with G_NORETURN

!3564 Fix gutils-user-database unit test

Translation updates:

Basque (Asier Sarasua Garmendia)
Czech (Vojtěch Perník)
Danish (Alan Mortensen)
English (United Kingdom) (Bruce Cowan)
Galician (Fran Dieguez)
Georgian (Ekaterine Papava)
German (Philipp Kiemle, Jürgen Benvenuti)
Hebrew (Yosef Or Boczko)
Hungarian (Balázs Úr)
Indonesian (Andika Triwidada)
Korean (Changwoo Ryu)
Lithuanian (Aurimas Černius)
Persian (Danial Behzadi)
Polish (Piotr Drąg)
Swedish (Anders Jonsson)
Turkish (Emin Tufan Çetin)
Ukrainian (Yuri Chornoivan)

GObject-introspection 1.78.0

Changes since 1.76
------------------

* Update the GIR data for GLib, GObject, and GIO
* Add GObject as a dependency for the Cairo GIR
* Add more tests for GI marshalling
* Update regression test suite
* Fix build on Windows for paths using `'\'` as a separator
* Support different prefix for finding GIR data
* Add `GI_GIR_PATH` environment variable for controlling GIR paths