RATIS-2520. Bump sonar-maven-plugin to 5.6.0.6792 #735

Job	Run time
CI / release / release	5m 29s
CI / build / build	1m 50s
CI / basic (checkstyle) / checkstyle	32s
CI / basic (findbugs) / findbugs	2m 31s
CI / unit (server) / unit (server)	16m 17s
CI / basic (rat) / rat	22s
CI / basic (author) / author	10s
CI / unit (misc) / unit (misc)	11m 21s
CI / unit (flaky) / unit (flaky)	3m 31s
CI / unit (grpc) / unit (grpc)	20m 2s
CI / repro / repro	1m 36s
CI / compile (11) / compile (11)	57s
CI / compile (17) / compile (17)	1m 6s
CI / compile (21) / compile (21)	1m 6s
CI / compile (8) / compile (8)	59s
CI / coverage	0s
	1h 7m 49s

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