Bump Go version to 1.16 (open-policy-agent#557)

Signed-off-by: manute <[email protected]>

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.13-alpine as base
+FROM golang:1.16-alpine as base
 ARG ARCH=amd64
 ARG VERSION
 ARG COMMIT

go.mod

@@ -1,6 +1,6 @@
 module github.com/open-policy-agent/conftest
 
-go 1.13
+go 1.16
 
 require (
 	cuelang.org/go v0.0.15

go.sum

@@ -194,7 +194,6 @@ github.com/bketelsen/crypt v0.0.3-0.20200106085610-5cbc8cc4026c/go.mod h1:MKsuJm
 github.com/blakesmith/ar v0.0.0-20190502131153-809d4375e1fb/go.mod h1:PkYb9DJNAwrSvRx5DYA+gUcOIgTGVMNkfSCbZM8cWpI=
 github.com/blang/semver v3.1.0+incompatible/go.mod h1:kRBLl5iJ+tD4TcOOxsy/0fnwebNt5EWlYSAyrTnjyyk=
 github.com/blang/semver v3.5.0+incompatible/go.mod h1:kRBLl5iJ+tD4TcOOxsy/0fnwebNt5EWlYSAyrTnjyyk=
-github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869 h1:DDGfHa7BWjL4YnC6+E63dPcxHo2sUxDIu8g3QgEJdRY=
 github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869/go.mod h1:Ekp36dRnpXw/yCqJaO+ZrUyxD+3VXMFFr56k5XYrpB4=
 github.com/bombsimon/wsl/v2 v2.0.0/go.mod h1:mf25kr/SqFEPhhcxW1+7pxzGlW+hIl/hYTKY95VwV8U=
 github.com/bombsimon/wsl/v2 v2.2.0/go.mod h1:Azh8c3XGEJl9LyX0/sFC+CKMc7Ssgua0g+6abzXN4Pg=
@@ -748,7 +747,6 @@ github.com/mitchellh/mapstructure v0.0.0-20160808181253-ca63d7c062ee/go.mod h1:F
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/mitchellh/mapstructure v1.3.1 h1:cCBH2gTD2K0OtLlv/Y5H01VQCqmlDxz30kS5Y5bqfLA=
 github.com/mitchellh/mapstructure v1.3.1/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
-github.com/mitchellh/osext v0.0.0-20151018003038-5e2d6d41470f h1:2+myh5ml7lgEU/51gbeLHfKGNfgEQQIWrlbdaOsidbQ=
 github.com/mitchellh/osext v0.0.0-20151018003038-5e2d6d41470f/go.mod h1:OkQIRizQZAeMln+1tSwduZz7+Af5oFlKirV/MSYes2A=
 github.com/moby/buildkit v0.8.2 h1:kvb0cLWss4mOhCxcXSTENzzA+t1JR1eIyXFhDrI+73g=
 github.com/moby/buildkit v0.8.2/go.mod h1:5PZi7ALzuxG604ggYSeN+rzC+CyJscuXS7WetulJr1Y=