Update refs to :soroban-dev to ref :future in readme (#550) #602

Job	Run time
arm64 / build-stellar-core	38s
arm64 / build-stellar-friendbot	4m 43s
arm64 / build-stellar-horizon	8m 5s
arm64 / build-stellar-soroban-rpc	3m 16s
amd64 / build-stellar-core	29s
amd64 / build-stellar-horizon	3m 4s
arm64 / build-rs-stellar-xdr	1m 52s
amd64 / build-rs-stellar-xdr	1m 45s
amd64 / build-stellar-friendbot	52s
amd64 / build-stellar-soroban-rpc	2m 10s
amd64 / build	6m 56s
arm64 / build	7m 43s
amd64 / test (testnet)	1m 27s
amd64 / test (testnet, --enable-soroban-rpc)	1m 50s
amd64 / test (pubnet)	3m 16s
amd64 / test (local)	1m 44s
amd64 / push-pr	0s
amd64 / test (local, --enable-soroban-rpc)	1m 47s
amd64 / push-release	44s
arm64 / test (testnet)	3m 31s
arm64 / test (testnet, --enable-soroban-rpc)	7m 3s
arm64 / push-pr	0s
arm64 / test (pubnet)	1m 25s
arm64 / test (local)	2m 27s
arm64 / test (local, --enable-soroban-rpc)	2m 51s
arm64 / push-release	51s
manifest / push	9s
complete	1s
	1h 10m 39s

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