HDFS-17821. Fix the SNN repeatedly checkpoint after fsimage transfer failure on one of the multiple NNs

[lfxy]

In our cluster with observer NNs, when the standby NN is doing a checkpoint and sending the fsimage to other NNs, if the sending fails of one NN due to network anomalies, NN restarts, or other exceptions, the standby will consider this Checkpoint as failed and does not update the lastCheckpointTime, and retry checkpoints.
However, the active or observer NNs which successfully received the fsimage has update their lastCheckpointTime, and the NN which receive fsimage failed don't update its lastCheckpointTime, resulting in inconsistent lastCheckpointTime across the NNs. This causes subsequent checkpoints to repeatedly fail to send fsimage to part or all active or observer NNs, because they do not satisfy the DFS_NAMENODE_CHECKPOINT_PERIOD_KEY condition.
Then the SNN will always failed to do checkpoint and repeat retry. I think that the SNN should consider the checkpoint successful and update its lastCheckpointTime if the fsimage transmission succeeds on at least half of the NNs.

[hadoop-yetus]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
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+1 💚	@author	0m 0s		The patch does not contain any @author tags.
+1 💚	test4tests	0m 0s		The patch appears to include 1 new or modified test files.
			_ trunk Compile Tests _
+1 💚	mvninstall	25m 47s		trunk passed
+1 💚	compile	0m 44s		trunk passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	compile	0m 39s		trunk passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	checkstyle	0m 39s		trunk passed
+1 💚	mvnsite	0m 44s		trunk passed
+1 💚	javadoc	0m 43s		trunk passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javadoc	1m 7s		trunk passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	spotbugs	1m 46s		trunk passed
+1 💚	shadedclient	22m 4s		branch has no errors when building and testing our client artifacts.
			_ Patch Compile Tests _
+1 💚	mvninstall	0m 38s		the patch passed
+1 💚	compile	0m 38s		the patch passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javac	0m 38s		the patch passed
+1 💚	compile	0m 34s		the patch passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	javac	0m 34s		the patch passed
+1 💚	blanks	0m 0s		The patch has no blanks issues.
+1 💚	checkstyle	0m 29s		the patch passed
+1 💚	mvnsite	0m 37s		the patch passed
+1 💚	javadoc	0m 34s		the patch passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javadoc	1m 1s		the patch passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	spotbugs	1m 40s		the patch passed
+1 💚	shadedclient	21m 45s		patch has no errors when building and testing our client artifacts.
			_ Other Tests _
+1 💚	unit	117m 28s		hadoop-hdfs in the patch passed.
+1 💚	asflicense	0m 30s		The patch does not generate ASF License warnings.
		209m 14s

Subsystem	Report/Notes
Docker	ClientAPI=1.51 ServerAPI=1.51 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-7876/2/artifact/out/Dockerfile
GITHUB PR	#7876
Optional Tests	dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient spotbugs checkstyle codespell detsecrets
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