Fix deadlock in InboundLedgers and NetworkOPs #4140

Job	Run time
dependencies (linux, gcc, Debug)	3m 12s
dependencies (linux, gcc, Release)	2m 9s
dependencies (linux, clang, Debug)	2m 48s
dependencies (linux, clang, Release)	2m 18s
conan	2m 47s
coverage (linux, gcc, Debug)	13m 7s
test (linux, gcc, Debug)	11m 24s
test (linux, gcc, Debug, -Dunity=ON)	7m 54s
test (linux, gcc, Release)	12m 37s
test (linux, gcc, Release, -Dunity=ON)	8m 23s
test (linux, clang, Debug)	9m 24s
test (linux, clang, Debug, -Dunity=ON)	6m 18s
test (linux, clang, Release)	11m 24s
test (linux, clang, Release, -Dunity=ON)	8m 24s
	1h 42m 9s

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