hardcoded v2 type urls in xds requests

[bennettdong]

Title: hardcoded v2 type urls in xds requests

Description:
In order to migrate to v3 API, loadTypeUrl functions are used to determine type url in discovery requests. However, I found that some files are still using v2 type url constants in this file. This means that even envoy is configured to use v3, it will still send requests for v2 resources.

Correct me if there is any magic actually doing the conversion somewhere.

[optional Relevant Links:]

envoy/source/common/router/scoped_rds.cc

Line 243 in 334724c

Envoy::Config::TypeUrl::get().RouteConfiguration);

envoy/source/common/router/scoped_rds.cc

Line 258 in 334724c

Envoy::Config::TypeUrl::get().RouteConfiguration);

envoy/source/common/upstream/cds_api_impl.cc

Lines 68 to 70 in 334724c

	cm_.adsMux()->pause(Config::TypeUrl::get().ClusterLoadAssignment);
	maybe_eds_resume = std::make_unique<Cleanup>(
	[this] { cm_.adsMux()->resume(Config::TypeUrl::get().ClusterLoadAssignment); });

envoy/source/common/upstream/cluster_manager_impl.cc

Lines 150 to 155 in 334724c

	cm_.adsMux()->paused(Config::TypeUrl::get().ClusterLoadAssignment)) {
	initializeSecondaryClusters();
	} else {
	cm_.adsMux()->pause(Config::TypeUrl::get().ClusterLoadAssignment);
	Cleanup eds_resume(
	[this] { cm_.adsMux()->resume(Config::TypeUrl::get().ClusterLoadAssignment); });

envoy/source/common/upstream/cluster_manager_impl.cc

Lines 752 to 754 in 334724c

	ads_mux_->pause(Config::TypeUrl::get().Cluster);
	} else if (previous_warming > 0 && warming_clusters_.empty()) {
	ads_mux_->resume(Config::TypeUrl::get().Cluster);

envoy/source/server/lds_api.cc

Lines 43 to 45 in 334724c

	cm_.adsMux()->pause(Config::TypeUrl::get().RouteConfiguration);
	maybe_eds_resume = std::make_unique<Cleanup>(
	[this] { cm_.adsMux()->resume(Config::TypeUrl::get().RouteConfiguration); });

envoy/source/server/server.cc

Lines 526 to 535 in 334724c

	cm.adsMux()->pause(Config::TypeUrl::get().RouteConfiguration);
	}
	ENVOY_LOG(info, "all clusters initialized. initializing init manager");
	init_manager.initialize(init_watcher_);
	// Now that we're execute all the init callbacks we can resume RDS
	// as we've subscribed to all the statically defined RDS resources.
	if (cm.adsMux()) {
	cm.adsMux()->resume(Config::TypeUrl::get().RouteConfiguration);

[mattklein123]

cc @lizan

[Shikugawa]

@lizan This problem may be resolved with getResourceName in #9649. So I will fix them after merging it.