Add itest for MinRelayFee check in tapd #1809

Job	Run time
check commits	50s
integration test	14m 52s
frontend tests on ubuntu-latest	4m 39s
backend build on ubuntu-latest	3m 11s
frontend tests on windows-latest	8m 39s
lint	2m 0s
RPC proto compilation check	3m 24s
backend build on windows-latest	19m 11s
frontend tests on macOS-latest	1m 49s
backend build on macOS-latest	7m 31s
check release notes updated	4s
unit tests	36s
unit-race	40s
	1h 7m 26s

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