Bump github.com/google/tink/go from 1.4.0-rc2 to 1.5.0

Bumps [github.com/google/tink/go](https://github.com/google/tink) from 1.4.0-rc2 to 1.5.0.
- [Release notes](https://github.com/google/tink/releases)
- [Commits](tink-crypto/tink@v1.4.0-rc2...v1.5.0)

Signed-off-by: dependabot-preview[bot] <[email protected]>

go.mod

@@ -12,8 +12,8 @@ require (
 	github.com/golang/mock v1.4.4
 	github.com/golang/protobuf v1.4.2
 	github.com/google/certificate-transparency-go v1.1.0 // indirect
-	github.com/google/go-cmp v0.5.0
-	github.com/google/tink/go v1.4.0-rc2
+	github.com/google/go-cmp v0.5.2
+	github.com/google/tink/go v1.5.0
 	github.com/google/trillian v1.3.10
 	github.com/grpc-ecosystem/go-grpc-middleware v1.2.0
 	github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0
@@ -28,13 +28,13 @@ require (
 	github.com/spf13/viper v1.7.0
 	go.uber.org/atomic v1.5.1 // indirect
 	gocloud.dev v0.20.0
-	golang.org/x/crypto v0.0.0-20200311171314-f7b00557c8c4
-	golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d
-	golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a
+	golang.org/x/crypto v0.0.0-20201002170205-7f63de1d35b0
+	golang.org/x/oauth2 v0.0.0-20200902213428-5d25da1a8d43
+	golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208
 	golang.org/x/time v0.0.0-20200416051211-89c76fbcd5d1
-	google.golang.org/api v0.29.0
-	google.golang.org/genproto v0.0.0-20200626011028-ee7919e894b5
-	google.golang.org/grpc v1.29.1
+	google.golang.org/api v0.32.0
+	google.golang.org/genproto v0.0.0-20200904004341-0bd0a958aa1d
+	google.golang.org/grpc v1.31.1
 	google.golang.org/protobuf v1.25.0
 	gopkg.in/yaml.v2 v2.2.8 // indirect
 )