clang-tidy: wrap test_utils.hpp in cpp

Introduced a temporary wrapper `.cpp` file that includes
`test_utils.hpp` to allow clang-tidy to analyze the header
in the correct compilation context.

clang-tidy was failing to resolve includes like `actions/action.hpp`
when run directly on `test_utils.hpp`, due to missing include path
context in the compilation database. This is a known limitation when
analyzing header files outside of a translation unit.

By wrapping the header in a `.cpp` file and running clang-tidy on
that instead, we ensure that all include paths and macros are
correctly applied, resolving false-positive errors and improving
static analysis reliability.

Change-Id: I9a72d14ab844c0b53eebea6229e0bc22ff8aa273
Signed-off-by: Jayanth Othayoth <ojayanth@gmail.com>
diff --git a/phosphor-regulators/test/test_utils.hpp b/phosphor-regulators/test/test_utils.hpp
index b3df87a..24084f8 100644
--- a/phosphor-regulators/test/test_utils.hpp
+++ b/phosphor-regulators/test/test_utils.hpp
@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 #include "action.hpp"
 #include "chassis.hpp"
 #include "configuration.hpp"