fix(deps): update module github.com/spf13/viper (v1.18.2 → v1.21.0)

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

.github/workflows/ci.yaml

@@ -12,7 +12,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+        uses: actions/checkout@v4
 
       - name: Setup Go
         uses: actions/setup-go@v5

.github/workflows/release.yaml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+        uses: actions/checkout@v4
         with:
           fetch-tags: true
           fetch-depth: 0

go.mod

@@ -3,5 +3,5 @@ module github.com/ivuorinen/tsm
 go 1.24
 
 require (
-	github.com/spf13/viper v1.18.2
+	github.com/spf13/viper v1.21.0
 )