bump github.com/fsouza/go-dockerclient to v1.12.0 #3699

Job	Run time
Basic Checks	3m 9s
Unit Tests	26m 57s
Integration Tests (raft)	12m 16s
Integration Tests (pvtdata)	12m 32s
Integration Tests (pvtdatapurge)	5m 1s
Integration Tests (ledger)	13m 9s
Integration Tests (lifecycle)	6m 11s
Integration Tests (e2e smartbft)	24m 44s
Integration Tests (discovery gossip devmode pluggable)	5m 42s
Integration Tests (gateway idemix pkcs11 configtx configtxlator)	17m 18s
Integration Tests (sbe nwo msp)	7m 35s
	2h 14m 34s

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