Update gobject-introspection to 1.66.0

1.66.0 - 2020-09-12
-------------------

* Support the gtk-doc action syntax :mr:`203`
* Meson fixes with glib and/or g-i is a subproject :mr:`206` :mr:`208`
* GITypeInfo storage type utility API :mr:`205`
* Meson: Fix build as subproject :mr:`214`
* Fixing XDG_DATA_DIRS logic :mr:`215`
* libgirepository: Add a couple missing nullable annotations :mr:`217` :mr:`225`
* dumper: Fix missing symbols in LTO case or with overridden symbol visibility settings :mr:`216`
* Documentation improvements: :mr:`220` :mr:`232`
* Remove old autoconf fallback code for the python tools :mr:`221`
* meson: Rename option `gi_cross_use_{host -> prebuilt}_gi` mr:`211`
* meson: Don't override finding executables when using pre-built tools. :mr:`212`
* meson: gir: add a dependency for g-ir-compiler for building .girs :mr:`228`
* meson: Use pkgconfig generator :mr:`207`
* Fix gi-dump-types.c to build on Windows :mr:`218`
* giscanner: parse block comments for members and fields :mr:`230`
* Add the notion of standalone doc sections :mr:`226`
* giscanner: Add support for using clang-cl :mr:`234`
* giscanner: Fix section matching for documentation :mr:`237`

(prlw1)