Test

fix typo about heartbeat. v5.0.220 v6.0.161 v7.0.23 #3698

Job	Run time
utest-regression-blackbox-test	9m 35s
cygwin64-cache	57s
multiple-arch-armv7	25m 48s
multiple-arch-aarch64	25m 40s
cygwin64	15m 28s
fast	1s
build-cross-arm	5m 46s
build-cross-aarch64	5m 31s
build-ubuntu16	3m 8s
build-centos7	4m 54s
build-ubuntu18	3m 16s
build-ubuntu20	3m 30s
coverage	3m 36s
multiple-arch-amd64	2m 23s
test-done	1s
	1h 49m 34s

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