Make 'https' the default GCS Scheme (#6361)

Summary:
The GCS Hive Connector is currently using insecure connection by default. It should behave like S3 and use secure connections by default. This change makes GCS use https as default scheme.

Fixes #6359

Pull Request resolved: #6361

Reviewed By: xiaoxmeng

Differential Revision: D48859558

Pulled By: kgpai

fbshipit-source-id: 0ee31da85f31e1fd1292dfae43b30f4744a992cf

velox/connectors/hive/HiveConfig.cpp

@@ -132,7 +132,7 @@ std::string HiveConfig::gcsEndpoint(const Config* config) {
 
 // static
 std::string HiveConfig::gcsScheme(const Config* config) {
-  return config->get<std::string>(kGCSScheme, std::string(""));
+  return config->get<std::string>(kGCSScheme, std::string("https"));
 }
 
 // static