Bump github.com/spf13/viper from 1.14.0 to 1.15.0

Bumps [github.com/spf13/viper](https://github.com/spf13/viper) from 1.14.0 to 1.15.0.
- [Release notes](https://github.com/spf13/viper/releases)
- [Commits](spf13/viper@v1.14.0...v1.15.0)

---
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

@@ -7,7 +7,7 @@ require (
 	github.com/criteo/haproxy-spoe-go v1.0.6
 	github.com/go-ldap/ldap/v3 v3.4.4
 	github.com/sirupsen/logrus v1.9.0
-	github.com/spf13/viper v1.14.0
+	github.com/spf13/viper v1.15.0
 	github.com/stretchr/testify v1.8.1
 	github.com/tebeka/selenium v0.9.9
 	github.com/vmihailenco/msgpack/v5 v5.3.5