chore(deps): update module github.com/go-viper/mapstructure to v2

Author: renovate[bot]

go.mod

@@ -2,7 +2,7 @@ module github.com/kilnfi/cardano-validator-watcher
 
 go 1.23
 
-replace github.com/mitchellh/mapstructure => github.com/go-viper/mapstructure v1.6.0
+replace github.com/mitchellh/mapstructure => github.com/go-viper/mapstructure/v2 v2.3.0
 
 require (
 	github.com/DATA-DOG/go-sqlmock v1.5.2