refactor: replace for loop over slice

cmd/package_commands.go

@@ -4,6 +4,7 @@ import (
 	"codeberg.org/Pata1704/system_setup_tool/internal/utils"
 	"fmt"
 	"os"
+	"slices"
 	"sort"
 
 	"github.com/spf13/cobra"
@@ -42,11 +43,9 @@ var addCmd = &cobra.Command{
 		} else {
 			packages := viper.GetStringSlice(fmt.Sprintf("package_managers.%s.packages", manager))
 
-			for _, pkg := range packages {
-				if pkg == name {
-					fmt.Printf("Package %s is already present in the configuration for %s\n", name, manager)
-					return
-				}
+			if slices.Contains(packages, name) {
+				fmt.Printf("Package %s is already present in the configuration for %s\n", name, manager)
+				return
 			}
 
 			packages = append(packages, name)