[custom channels]: Fix bandwidth manager and other bugs #3557

Job	Run time
Docker build check	3m 52s
Format check	2m 35s
cross compilation	6m 55s
Compilation check	4m 55s
run itests	12m 10s
run itests postgres	20m 39s
Lint check	4m 46s
migration version check	10s
go mod check	2m 41s
RPC check	3m 20s
run LiT tests	3m 46s
sample configuration check	2m 45s
Sqlc check	2m 40s
test vector check	3m 3s
run unit tests (unit-race)	11m 34s
run unit tests (unit-cover)	4m 24s
run unit tests (unit dbbackend=postgres)	6m 5s
finish	5s
	1h 36m 25s

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