chore(deps): bump github.com/spf13/viper from 1.19.0 to 1.21.0

Bumps [github.com/spf13/viper](https://github.com/spf13/viper) from 1.19.0 to 1.21.0.
- [Release notes](https://github.com/spf13/viper/releases)
- [Commits](spf13/viper@v1.19.0...v1.21.0)

---
updated-dependencies:
- dependency-name: github.com/spf13/viper
  dependency-version: 1.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

go.mod

@@ -1,6 +1,6 @@
 module gatehill.io/imposter
 
-go 1.23.8
+go 1.24.0
 
 require (
 	github.com/araddon/dateparse v0.0.0-20210429162001-6b43995a97de
@@ -14,8 +14,8 @@ require (
 	github.com/shirou/gopsutil/v4 v4.25.6
 	github.com/sirupsen/logrus v1.9.3
 	github.com/spf13/cobra v1.9.1
-	github.com/spf13/viper v1.19.0
-	github.com/stretchr/testify v1.10.0
+	github.com/spf13/viper v1.21.0
+	github.com/stretchr/testify v1.11.1
 	gopkg.in/yaml.v2 v2.4.0
 	sigs.k8s.io/yaml v1.6.0
 )
@@ -31,20 +31,18 @@ require (
 	github.com/ebitengine/purego v0.8.4 // indirect
 	github.com/fatih/color v1.15.0 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
-	github.com/fsnotify/fsnotify v1.7.0 // indirect
+	github.com/fsnotify/fsnotify v1.9.0 // indirect
 	github.com/go-logr/logr v1.4.2 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/go-ole/go-ole v1.2.6 // indirect
+	github.com/go-viper/mapstructure/v2 v2.4.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
-	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/jmespath/go-jmespath v0.4.0 // indirect
 	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
-	github.com/magiconair/properties v1.8.7 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.19 // indirect
 	github.com/mattn/go-runewidth v0.0.16 // indirect
-	github.com/mitchellh/mapstructure v1.5.0 // indirect
 	github.com/moby/docker-image-spec v1.3.1 // indirect
 	github.com/moby/sys/atomicwriter v0.1.0 // indirect
 	github.com/moby/term v0.5.0 // indirect
@@ -53,17 +51,16 @@ require (
 	github.com/olekukonko/ll v0.0.9 // indirect
 	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/opencontainers/image-spec v1.0.2 // indirect
-	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.4 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/power-devops/perfstat v0.0.0-20210106213030-5aafc221ea8c // indirect
 	github.com/rivo/uniseg v0.2.0 // indirect
-	github.com/sagikazarmark/locafero v0.4.0 // indirect
-	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 v1.6.0 // indirect
-	github.com/spf13/pflag v1.0.6 // indirect
+	github.com/sagikazarmark/locafero v0.11.0 // indirect
+	github.com/sourcegraph/conc v0.3.1-0.20240121214520-5f936abd7ae8 // indirect
+	github.com/spf13/afero v1.15.0 // indirect
+	github.com/spf13/cast v1.10.0 // indirect
+	github.com/spf13/pflag v1.0.10 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
 	github.com/tklauser/go-sysconf v0.3.12 // indirect
 	github.com/tklauser/numcpus v0.6.1 // indirect
@@ -75,16 +72,14 @@ require (
 	go.opentelemetry.io/otel/metric v1.35.0 // indirect
 	go.opentelemetry.io/otel/sdk v1.35.0 // indirect
 	go.opentelemetry.io/otel/trace v1.35.0 // indirect
-	go.uber.org/atomic v1.9.0 // indirect
-	go.uber.org/multierr v1.9.0 // indirect
 	go.yaml.in/yaml/v2 v2.4.2 // indirect
-	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
-	golang.org/x/mod v0.22.0 // indirect
-	golang.org/x/sync v0.11.0 // indirect
-	golang.org/x/sys v0.30.0 // indirect
-	golang.org/x/text v0.22.0 // indirect
-	golang.org/x/tools v0.21.1-0.20240508182429-e35e4ccd0d2d // indirect
-	gopkg.in/ini.v1 v1.67.0 // indirect
+	go.yaml.in/yaml/v3 v3.0.4 // indirect
+	golang.org/x/mod v0.26.0 // indirect
+	golang.org/x/sync v0.16.0 // indirect
+	golang.org/x/sys v0.34.0 // indirect
+	golang.org/x/text v0.28.0 // indirect
+	golang.org/x/time v0.13.0 // indirect
+	golang.org/x/tools v0.35.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	gotest.tools/v3 v3.5.1 // indirect
 )