build(deps): bump github.com/spf13/viper from 1.3.0 to 1.3.1

Bumps [github.com/spf13/viper](https://github.com/spf13/viper) from 1.3.0 to 1.3.1.
- [Release notes](https://github.com/spf13/viper/releases)
- [Commits](https://github.com/spf13/viper/compare/v1.3.0...v1.3.1)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Gopkg.lock

@@ -346,12 +346,12 @@
   version = "v1.0.3"
 
 [[projects]]
-  digest = "1:34c2a71c3317bd76711f66330d7846597bea8cd26c9df5bfd4603d156503e1bf"
+  digest = "1:de37e343c64582d7026bf8ab6ac5b22a72eac54f3a57020db31524affed9f423"
   name = "github.com/spf13/viper"
   packages = ["."]
   pruneopts = "UT"
-  revision = "41cd1c3aa32b2685fae6c296e6f044bc68922c0e"
-  version = "v1.3.0"
+  revision = "6d33b5a963d922d182c91e8a1c88d81fd150cfd4"
+  version = "v1.3.1"
 
 [[projects]]
   digest = "1:03aa6e485e528acb119fb32901cf99582c380225fc7d5a02758e08b180cb56c3"

Gopkg.toml

@@ -95,7 +95,7 @@
 
 [[constraint]]
   name = "github.com/spf13/viper"
-  version = "=1.3.0"
+  version = "=1.3.1"
 
 [[constraint]]
   branch = "v1"