Test

Fix GH-21688: SEGV in C14N on empty HTMLDocument. #1573

Job	Run time
Generate Matrix	9s
Suite / ALPINE_X64_ASAN_DEBUG_ZTS	31m 51s
Suite / LINUX_X64_ASAN_DEBUG_ZTS	46m 26s
Suite / WINDOWS_X64_ZTS	33m 21s
Suite / MACOS_ARM64_DEBUG_NTS	18m 34s
Suite / LINUX_X32_DEBUG_ZTS	13m 36s
Suite / BENCHMARKING	16m 55s
Suite / FREEBSD_NTS	11m 42s
Suite / LINUX_X64_RELEASE_NTS	25m 13s
Suite / COVERAGE	0s
Suite / OPCACHE_VARIATION	0s
Suite / MSAN	0s
Suite / LINUX_PPC64_ASAN_DEBUG_ZTS	0s
Suite / SOLARIS	0s
Suite / PECL	0s
Suite / COMMUNITY_${{ matrix.type }}	0s
Suite / LIBMYSQLCLIENT	0s
	3h 17m 47s

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