clusterer: Fix potential AB/BA sync deadlock on DONOR nodes #1619

Job	Run time
build_and_test (gcc, ubuntu-20.04)	7m 36s
build_and_test (clang, ubuntu-20.04)	6m 58s
build_and_test (gcc-9, ubuntu-20.04)	7m 39s
build_and_test (gcc-10, ubuntu-20.04)	7m 3s
build_and_test (clang-9, ubuntu-20.04)	6m 44s
build_and_test (clang-10, ubuntu-20.04)	6m 21s
build_and_test (gcc, ubuntu-22.04)	9m 49s
build_and_test (clang, ubuntu-22.04)	7m 18s
build_and_test (gcc-11, ubuntu-22.04)	9m 18s
build_and_test (gcc-12, ubuntu-22.04)	10m 50s
build_and_test (clang-11, ubuntu-22.04)	6m 57s
build_and_test (clang-12, ubuntu-22.04)	7m 29s
build_and_test (clang-13, ubuntu-22.04)	7m 7s
build_and_test (clang-14, ubuntu-22.04)	7m 3s
build_and_test (clang-15, ubuntu-22.04)	7m 31s
build_and_test (gcc-arm64-qemu-cross, ubuntu-22.04)	1h 4m 20s
build_and_test (gcc-arm32-qemu-cross, ubuntu-22.04)	29m 34s
build_and_test (clang-arm64-qemu-cross, ubuntu-22.04)	2h 5m 20s
build_and_test (clang-arm32-qemu-cross, ubuntu-22.04)	33m 6s
notify	4s
	6h 8m 7s

Provide feedback