remove testify dependency

go.mod

@@ -9,7 +9,6 @@ require (
 	github.com/hashicorp/hc-install v0.3.1
 	github.com/hashicorp/terraform-json v0.13.0
 	github.com/sergi/go-diff v1.2.0
-	github.com/stretchr/testify v1.7.0
 	github.com/zclconf/go-cty v1.10.0
 	github.com/zclconf/go-cty-debug v0.0.0-20191215020915-b22d67c1ba0b
 )
@@ -18,7 +17,6 @@ require (
 	github.com/Microsoft/go-winio v0.4.16 // indirect
 	github.com/ProtonMail/go-crypto v0.0.0-20210428141323-04723f9f07d7 // indirect
 	github.com/acomagu/bufpipe v1.0.3 // indirect
-	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/emirpasic/gods v1.12.0 // indirect
 	github.com/go-git/gcfg v1.5.0 // indirect
 	github.com/go-git/go-billy/v5 v5.3.1 // indirect
@@ -28,13 +26,11 @@ require (
 	github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 // indirect
 	github.com/kevinburke/ssh_config v0.0.0-20201106050909-4977a11b4351 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
-	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/xanzy/ssh-agent v0.3.0 // indirect
 	golang.org/x/crypto v0.0.0-20210616213533-5ff15b29337e // indirect
 	golang.org/x/net v0.0.0-20210326060303-6b1517762897 // indirect
 	golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1 // indirect
 	golang.org/x/text v0.3.5 // indirect
 	golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 // indirect
 	gopkg.in/warnings.v0 v0.1.2 // indirect
-	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
 )