[fuchsia] Migrate to new RealmBuilder API (#39205)

See https://fxrev.dev/793422.

Missed in d85ec02b0d25f8b3c2a45d1879846bbe9d19ab33,
ade610ec88b550ccef5f25b169d574f3fe15a3ab and
6fe9861be30f8fa0ec2afea893d8a8acc6276f77.

shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-test.cc

diff --git a/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-test.cc b/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-test.cc
index e872e92..5166cca 100644
--- a/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-test.cc
+++ b/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-test.cc
@@ -226,7 +226,7 @@
 
     // Get the display dimensions.
     FML_LOG(INFO) << "Waiting for scenic display info";
-    scenic_ = realm_root()->template Connect<fuchsia::ui::scenic::Scenic>();
+    scenic_ = realm_root()->component().Connect<fuchsia::ui::scenic::Scenic>();
     scenic_->GetDisplayInfo([this](fuchsia::ui::gfx::DisplayInfo display_info) {
       display_width_ = display_info.width_in_px;
       display_height_ = display_info.height_in_px;
@@ -345,7 +345,7 @@
 
     // Get the display dimensions.
     FML_LOG(INFO) << "Waiting for scenic display info";
-    scenic_ = realm_root()->template Connect<fuchsia::ui::scenic::Scenic>();
+    scenic_ = realm_root()->component().Connect<fuchsia::ui::scenic::Scenic>();
     scenic_->GetDisplayInfo([this](fuchsia::ui::gfx::DisplayInfo display_info) {
       display_width_ = display_info.width_in_px;
       display_height_ = display_info.height_in_px;