Update CloudEvents sdk-go to v2.0.0 and update-deps.

go.mod

@@ -4,9 +4,11 @@ go 1.13
 
 require (
 	cloud.google.com/go v0.47.0 // indirect
+	contrib.go.opencensus.io/exporter/ocagent v0.6.0 // indirect
+	contrib.go.opencensus.io/exporter/prometheus v0.1.0 // indirect
 	contrib.go.opencensus.io/exporter/stackdriver v0.12.8 // indirect
 	github.com/GoogleCloudPlatform/cloud-builders/gcs-fetcher v0.0.0-20191203181535-308b93ad1f39
-	github.com/cloudevents/sdk-go/v2 v2.0.0-RC3
+	github.com/cloudevents/sdk-go/v2 v2.0.0
 	github.com/ghodss/yaml v1.0.0
 	github.com/go-openapi/spec v0.19.4 // indirect
 	github.com/golang/protobuf v1.3.3 // indirect
@@ -23,8 +25,6 @@ require (
 	github.com/markbates/inflect v1.0.4 // indirect
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/nbio/st v0.0.0-20140626010706-e9e8d9816f32 // indirect
-	github.com/onsi/ginkgo v1.10.1 // indirect
-	github.com/onsi/gomega v1.7.0 // indirect
 	github.com/pkg/errors v0.9.1
 	github.com/prometheus/common v0.7.0 // indirect
 	github.com/shurcooL/githubv4 v0.0.0-20191102174205-af46314aec7b // indirect