abseil-cpp: Update to version 20250814.0

abseil-cpp: Update to version 20250814.0

- Update from version 20250127.0 to 20250814.0
- Update of rootfile
- Changelog
    20250814.0
	What's New:
	    absl::Mutex now contains lower-case method names like lock() and
	     shared_lock() to align with standard C++ mutex methods. This allows
	     absl::Mutex to be used with std::scoped_lock and friends. The old names
	     are still present but may be removed in a future release.
	    The RAII Mutex-locker types like absl::MutexLock, absl::ReaderMutexLock,
	     and friends now accept references to absl::Mutex. The pointer-accepting
	     constructors are now deprecated, and may be removed in a future release.
	Breaking Changes:
	    Nullability template types, which were deprecated in the May 2025 release,
	     have been removed.
	    absl::string_view(nullptr), which is undefined behavior according to the
	     C++ standard, now triggers an assert failure. Note that unless you
	     changed absl/base/options.h, absl::string_view is an alias for
	     std::string_view, so by default you will be inheriting the behavior of
	     your standard library instead of using the Abseil implementation.
	    Abseil's hash tables now require a hash function that has a return type
	     with size >= sizeof(size_t).
	Known Issues
	    CHECK_<OP> is failing to compile on older versions of GCC when one of the
	     arguments is a C-style string. This is fixed by ba9a180 and will be
	     included in a future patch release.
    20250512.1
	What's New:
	    The polyfill types absl::any, absl::optional, and absl::variant are now
	     aliases for std::any, std::optional, and std::variant in all builds.
	     (Note that the polyfill implementation absl::string_view remains at the
	     present time, but it defaults to being an alias std::string_view in all
	     builds.)
	    Added absl::FastTypeId<Type>(), which evaluates at compile-time to a
	     unique id for the passed-in type.
	    Added absl::endian and absl::byteswap polyfills (25bce12).
	Breaking Changes:
	    Abseil now requires at least C++17 and follows Google's Foundational C++
	     Support Policy. See this table for a list of currently supported versions
	     compilers, platforms, and build tools.
	    Nullability template types are deprecated and will be removed in a future
	     release. The macro-style annotations (absl_nonnull, absl_nullable) should
	     be used instead (caf854d).
	Known Issues
	    None known at this time.
    20250512.0
	What's New:
	    The polyfill types absl::any, absl::optional, and absl::variant are now
	     aliases for std::any, std::optional, and std::variant in all builds.
	     (Note that the polyfill implementation absl::string_view remains at the
	     present time, but it defaults to being an alias std::string_view in all
	     builds.)
	    Added absl::FastTypeId<Type>(), which evaluates at compile-time to a
	     unique id for the passed-in type.
	    Added absl::endian and absl::byteswap polyfills (25bce12).
	Breaking Changes:
	    Abseil now requires at least C++17 and follows Google's Foundational C++
	     Support Policy. See this table for a list of currently supported versions
	     compilers, platforms, and build tools.
	    Nullability template types are deprecated and will be removed in a future
	     release. The macro-style annotations (absl_nonnull, absl_nullable) should
	     be used instead (caf854d).
	Known Issues
	    This release fails to compile with GCC7 and GCC8. This is fixed in
	     20250512.1.
    20250127.1
	What's New:
	    Added support for Bazel 8.0
	    Added support for Bazel Platforms for better portability
	    Added ABSL_ATTRIBUTE_VIEW and ABSL_ATTRIBUTE_OWNER for diagnosing certain
	     lifetime issues
	    Many performance improvements
	    A security issue in hash container create/resize has been fixed. Note that
	     the latest patch releases for previous LTS versions also address this issue.
	Breaking Changes:
	    Bazel BUILD files now reference repositories by their canonical names from
	     the Bazel Central Registry. For example, Abseil is now @abseil-cpp
	     instead of @com_google_absl, and GoogleTest is now @googletest instead of
	     @com_google_googletest. Users still using the old WORKSPACE system may
	     need to use repo_mapping on repositories that still use the old names.
	     See 90a7ba6 for an example.
	Other:
	    This will be the last release to support C++14. Future releases will
	     require at least C++17.
	Known Issues
	    None known at this time.

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>