Bump github.com/spf13/viper from 1.8.1 to 1.9.0

Bumps [github.com/spf13/viper](https://github.com/spf13/viper) from 1.8.1 to 1.9.0.
- [Release notes](https://github.com/spf13/viper/releases)
- [Commits](https://github.com/spf13/viper/compare/v1.8.1...v1.9.0)

---
updated-dependencies:
- dependency-name: github.com/spf13/viper
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

go.mod

@@ -30,7 +30,7 @@ require (
 	github.com/lestrrat-go/jwx v1.2.6
 	github.com/matoous/go-nanoid v1.5.0
 	github.com/mattn/go-sqlite3 v2.0.3+incompatible
-	github.com/mattn/go-zglob v0.0.3 // indirect
+	github.com/mattn/go-zglob v0.0.3
 	github.com/microcosm-cc/bluemonday v1.0.15
 	github.com/mileusna/useragent v1.0.2
 	github.com/oklog/run v1.1.0
@@ -40,7 +40,7 @@ require (
 	github.com/robfig/cron/v3 v3.0.1
 	github.com/sirupsen/logrus v1.8.1
 	github.com/spf13/cobra v1.2.1
-	github.com/spf13/viper v1.8.1
+	github.com/spf13/viper v1.9.0
 	github.com/stretchr/testify v1.7.0
 	github.com/unrolled/secure v1.0.9
 	github.com/xrash/smetrics v0.0.0-20200730060457-89a2a8a1fb0b