Bump to viper 1.8.1 (#1433)

Author: jpmcb

go.mod

@@ -6,6 +6,6 @@ require (
 	github.com/cpuguy83/go-md2man/v2 v2.0.0
 	github.com/inconshreveable/mousetrap v1.0.0
 	github.com/spf13/pflag v1.0.5
-	github.com/spf13/viper v1.8.0
+	github.com/spf13/viper v1.8.1
 	gopkg.in/yaml.v2 v2.4.0
 )

go.sum

@@ -224,8 +224,8 @@ github.com/spf13/jwalterweatherman v1.1.0 h1:ue6voC5bR5F8YxI5S67j9i582FU4Qvo2bmq
 github.com/spf13/jwalterweatherman v1.1.0/go.mod h1:aNWZUN0dPAAO/Ljvb5BEdw96iTZ0EXowPYD95IqWIGo=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
-github.com/spf13/viper v1.8.0 h1:QRwDgoG8xX+kp69di68D+YYTCWfYEckbZRfUlEIAal0=
-github.com/spf13/viper v1.8.0/go.mod h1:o0Pch8wJ9BVSWGQMbra6iw0oQ5oktSIBaujf1rJH9Ns=
+github.com/spf13/viper v1.8.1 h1:Kq1fyeebqsBfbjZj4EL7gj2IO0mMaiyjYUWcUsl2O44=
+github.com/spf13/viper v1.8.1/go.mod h1:o0Pch8wJ9BVSWGQMbra6iw0oQ5oktSIBaujf1rJH9Ns=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=