chore: tidy dependencies

Author: clareliguori

go.mod

@@ -3,26 +3,21 @@ module github.com/awslabs/aws-lambda-container-image-converter
 go 1.13
 
 require (
-	github.com/DataDog/zstd v1.4.0 // indirect
-	github.com/Nvveen/Gotty v0.0.0-20120604004816-cd527374f1e5 // indirect
 	github.com/aws/aws-sdk-go v1.32.13
 	github.com/containers/image/v5 v5.5.1
 	github.com/dsnet/compress v0.0.1 // indirect
 	github.com/frankban/quicktest v1.7.2 // indirect
 	github.com/golang/mock v1.4.3
 	github.com/golang/snappy v0.0.1 // indirect
-	github.com/klauspost/cpuid v1.2.1 // indirect
 	github.com/mattn/go-zglob v0.0.2
 	github.com/mholt/archiver v3.1.1+incompatible
 	github.com/nwaples/rardecode v1.0.0 // indirect
 	github.com/opencontainers/go-digest v1.0.0
 	github.com/opencontainers/image-spec v1.0.2-0.20190823105129-775207bd45b6
 	github.com/pierrec/lz4 v2.4.0+incompatible // indirect
 	github.com/pkg/errors v0.9.1
-	github.com/spf13/pflag v1.0.3 // indirect
 	github.com/stretchr/testify v1.6.1
 	github.com/urfave/cli v1.22.4
 	github.com/xi2/xz v0.0.0-20171230120015-48954b6210f8 // indirect
 	gopkg.in/yaml.v2 v2.3.0
-	k8s.io/client-go v11.0.0+incompatible // indirect
 )