build(deps): bump github.com/spf13/viper in /frontend

Bumps [github.com/spf13/viper](https://github.com/spf13/viper) from 1.18.0 to 1.18.1.
- [Release notes](https://github.com/spf13/viper/releases)
- [Commits](https://github.com/spf13/viper/compare/v1.18.0...v1.18.1)

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

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

frontend/go.mod

@@ -8,7 +8,7 @@ require (
 	github.com/jarcoal/httpmock v1.3.1
 	github.com/magiconair/properties v1.8.7
 	github.com/spf13/pflag v1.0.5
-	github.com/spf13/viper v1.18.0
+	github.com/spf13/viper v1.18.1
 )
 
 require (