Update terraform to 0.13

go.mod

@@ -1,38 +1,21 @@
 module github.com/nauxliu/terraform-provider-cronitor
 
-go 1.12
+go 1.14
 
 require (
 	cloud.google.com/go v0.47.0 // indirect
 	cloud.google.com/go/storage v1.1.1 // indirect
-	github.com/aws/aws-sdk-go v1.25.14 // indirect
 	github.com/golang/groupcache v0.0.0-20191002201903-404acd9df4cc // indirect
-	github.com/google/go-cmp v0.3.1 // indirect
-	github.com/hashicorp/go-cleanhttp v0.5.1 // indirect
-	github.com/hashicorp/go-hclog v0.9.2 // indirect
-	github.com/hashicorp/go-plugin v1.0.1 // indirect
-	github.com/hashicorp/go-version v1.2.0 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
-	github.com/hashicorp/hcl2 v0.0.0-20191002203319-fb75b3253c80 // indirect
 	github.com/hashicorp/hil v0.0.0-20190212132231-97b3a9cdfa93 // indirect
-	github.com/hashicorp/terraform v0.12.10
+	github.com/hashicorp/terraform v0.13.0
 	github.com/hashicorp/yamux v0.0.0-20190923154419-df201c70410d // indirect
 	github.com/json-iterator/go v1.1.7
 	github.com/jstemmer/go-junit-report v0.9.1 // indirect
-	github.com/mattn/go-colorable v0.1.4 // indirect
-	github.com/mattn/go-isatty v0.0.10 // indirect
-	github.com/mitchellh/reflectwalk v1.0.1 // indirect
-	github.com/spf13/afero v1.2.2 // indirect
 	github.com/ulikunitz/xz v0.5.6 // indirect
 	github.com/vmihailenco/msgpack v4.0.4+incompatible // indirect
 	go.opencensus.io v0.22.1 // indirect
-	golang.org/x/build v0.0.0-20190111050920-041ab4dc3f9d // indirect
-	golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 // indirect
 	golang.org/x/exp v0.0.0-20191014171548-69215a2ee97e // indirect
-	golang.org/x/net v0.0.0-20191014212845-da9a3fd4c582 // indirect
-	golang.org/x/sys v0.0.0-20191010194322-b09406accb47 // indirect
-	golang.org/x/tools v0.0.0-20191017101817-846f856e7d71 // indirect
 	google.golang.org/api v0.11.0 // indirect
 	google.golang.org/appengine v1.6.5 // indirect
-	google.golang.org/grpc v1.24.0 // indirect
 )