girepository: Update gi-compile-repository and use it to compile GIRs

Adapt gi-compile-repository sources to compile against the updated
libgirepository that is included with GLib.

This also renames "g-ir-compiler" to "gi-compile-repository" to avoid
overwriting the existing binary and to simplify the binary name going
forward.

girepository/tests/meson.build

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# SPDX-FileCopyrightText: 2024 GNOME Foundation
+
 girepository_tests = {
   'cmph-bdz': {
     'dependencies': [cmph_dep],