Log Message:
Update libpeas to 1.6.0 (PR#46921)

* Remove the vala demo plugin
* Add min required and max allowed version for glib and Gdk
* Warn if activate or deactivate are not implemented
* Find extension construct properties also in interface prerequisites
* Fix interface sorting in GJS and Seed
* Added peas_engine_prepend_search_path
* Added peas_plugin_info_get_external_data
* Misc bugfixes