Include logical annotation in method ColumnDescriptor::ToString()

cpp/src/parquet/schema-test.cc

@@ -591,6 +591,7 @@ TEST(TestColumnDescriptor, TestAttrs) {
   path: 
   physical_type: BYTE_ARRAY
   logical_type: UTF8
+  logical_annotation: String
   max_definition_level: 4
   max_repetition_level: 1
 })",
@@ -610,6 +611,7 @@ TEST(TestColumnDescriptor, TestAttrs) {
   path: 
   physical_type: FIXED_LEN_BYTE_ARRAY
   logical_type: DECIMAL
+  logical_annotation: Decimal(precision=10, scale=4)
   max_definition_level: 4
   max_repetition_level: 1
   length: 12

cpp/src/parquet/schema.cc

@@ -871,6 +871,7 @@ std::string ColumnDescriptor::ToString() const {
      << "  path: " << path()->ToDotString() << std::endl
      << "  physical_type: " << TypeToString(physical_type()) << std::endl
      << "  logical_type: " << LogicalTypeToString(logical_type()) << std::endl
+     << "  logical_annotation: " << logical_annotation()->ToString() << std::endl
      << "  max_definition_level: " << max_definition_level() << std::endl
      << "  max_repetition_level: " << max_repetition_level() << std::endl;