Bump github.com/spf13/viper from 1.17.0 to 1.18.1

Bumps [github.com/spf13/viper](https://github.com/spf13/viper) from 1.17.0 to 1.18.1.
- [Release notes](https://github.com/spf13/viper/releases)
- [Commits](spf13/viper@v1.17.0...v1.18.1)

---
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/deepmap/oapi-codegen v1.16.2
 	github.com/oapi-codegen/runtime v1.1.0
 	github.com/spf13/cobra v1.8.0
-	github.com/spf13/viper v1.17.0
+	github.com/spf13/viper v1.18.1
 	golang.org/x/net v0.19.0
 )
 
@@ -25,7 +25,7 @@ require (
 	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
 	github.com/sourcegraph/conc v0.3.0 // indirect
 	github.com/spf13/afero v1.11.0 // indirect
-	github.com/spf13/cast v1.5.1 // indirect
+	github.com/spf13/cast v1.6.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect