client-sdk/go: Bump the imports

The runtime-sdk uses a newer version of oasis-core, so bring it back
into sync.

client-sdk/go/go.mod

@@ -5,13 +5,17 @@ go 1.16
 // Should be synced with Oasis Core as replace directives are not propagated.
 replace (
 	github.com/tendermint/tendermint => github.com/oasisprotocol/tendermint v0.34.9-oasis2
-	golang.org/x/crypto/curve25519 => github.com/oasisprotocol/ed25519/extra/x25519 v0.0.0-20210127160119-f7017427c1ea
-	golang.org/x/crypto/ed25519 => github.com/oasisprotocol/ed25519 v0.0.0-20210127160119-f7017427c1ea
+	golang.org/x/crypto/curve25519 => github.com/oasisprotocol/curve25519-voi/primitives/x25519 v0.0.0-20210505121811-294cf0fbfb43
+	golang.org/x/crypto/ed25519 => github.com/oasisprotocol/curve25519-voi/primitives/ed25519 v0.0.0-20210505121811-294cf0fbfb43
 )
 
 require (
 	github.com/btcsuite/btcd v0.21.0-beta
-	github.com/oasisprotocol/oasis-core/go v0.2101.1-0.20210504072550-da25d939a3d4
+	github.com/fxamacker/cbor/v2 v2.2.1-0.20210517032302-bdd38cd1c8c0 // indirect
+	github.com/oasisprotocol/oasis-core/go v0.2101.1-0.20210517160830-c287752b61b7
+	github.com/prometheus/common v0.24.0 // indirect
 	github.com/stretchr/testify v1.7.0
+	golang.org/x/net v0.0.0-20210510120150-4163338589ed // indirect
+	golang.org/x/sys v0.0.0-20210514084401-e8d321eab015 // indirect
 	google.golang.org/grpc v1.37.0
 )