Add test_class_sh_property_non_owning to CMakeLists.txt

[rwgk]

Description

Fixes oversight in PR #4586.

Suggested changelog entry:

[rwgk]

@wangxf123456 I'll go ahead merge this trivial PR, to make it a little easier to run global testing for smart_holder, and keep pywrapcc and smart_holder in sync.

[rwgk]

For reasons I don't understand, the https://github.com/pybind/pybind11/pull/4590/files view here is misleading. The actual diff (git show 4f3a1a82318979147bfbdbf464774c316e555a17) is just this:

diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 3a1ce894..12b25808 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -130,6 +130,7 @@ set(PYBIND11_TEST_FILES
     test_class_sh_mi_thunks
     test_class_sh_module_local.py
     test_class_sh_property
+    test_class_sh_property_non_owning
     test_class_sh_shared_ptr_copy_move
     test_class_sh_trampoline_basic
     test_class_sh_trampoline_self_life_support
diff --git a/tests/test_class_sh_property_non_owning.cpp b/tests/test_class_sh_property_non_owning.cpp
index 5be72007..d15bf23a 100644
--- a/tests/test_class_sh_property_non_owning.cpp
+++ b/tests/test_class_sh_property_non_owning.cpp
@@ -27,10 +27,10 @@ private:
     std::vector<DataField> vec;

 public:
-    DataFieldsHolder(std::size_t vec_size) {
+    explicit DataFieldsHolder(std::size_t vec_size) {
         for (std::size_t i = 0; i < vec_size; i++) {
             int i11 = static_cast<int>(i) * 11;
-            vec.push_back(DataField(13 + i11, 14 + i11, 15 + i11));
+            vec.emplace_back(13 + i11, 14 + i11, 15 + i11);
         }
     }