Add terraform_map_duplicate_keys rule to presets

Author: wata727

rules/preset.go

@@ -11,6 +11,7 @@ var PresetRules = map[string][]tflint.Rule{
 		NewTerraformDocumentedOutputsRule(),
 		NewTerraformDocumentedVariablesRule(),
 		NewTerraformEmptyListEqualityRule(),
+		NewTerraformMapDuplicateKeysRule(),
 		NewTerraformModulePinnedSourceRule(),
 		NewTerraformModuleVersionRule(),
 		NewTerraformNamingConventionRule(),
@@ -27,6 +28,7 @@ var PresetRules = map[string][]tflint.Rule{
 		NewTerraformDeprecatedInterpolationRule(),
 		NewTerraformDeprecatedLookupRule(),
 		NewTerraformEmptyListEqualityRule(),
+		NewTerraformMapDuplicateKeysRule(),
 		NewTerraformModulePinnedSourceRule(),
 		NewTerraformModuleVersionRule(),
 		NewTerraformRequiredProvidersRule(),