at-spi2-core: upgrade 2.52.0 -> 2.54.0

at-spi2-core: upgrade 2.52.0 -> 2.54.0

Changelog:
==========
* Make ATSPI_ROLE_PUSH_BUTTON an enum value again.
* atk: Align button role with AT-SPI one.
* Fix warning when atspi_event_quit is called multiple times.
* tests: Clean up test application on SIGABRT/SIGSEGV.
* Set (allow-none) for nullable parameters to atspi_match_rule_new.
* collection: Allow specifying specific action names in match rules.
* atk-adaptor: For collections, don't return objects with 0 actions as
  supporting AtkAction.
* Rename ATSPI_ROLE_PUSH_BUTTON to ATSPI_ROLE_BUTTON.
* Replace disable_p2p with an ATSPI_DISABLE_P2P environment variable.
* Drop use of deprecated eaves-dropping option in dbus configuration
* Notify about HelpText attribute change.
* Fix possible double unref in add_accessible_from_iter.
* tests: Fix missing declaration for getpid().

Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>