Adds MaterialEditor RHI launch tests (#3558)

* adds MaterialEditor RHI launch tests

* add explicit editor_script parameter to the launch_and_validate_results() call

Signed-off-by: jromnoa <jromnoa@amazon.com>

AutomatedTesting/Gem/PythonTests/atom_renderer/test_Atom_GPUTests.py

@@ -181,3 +181,39 @@ class TestPerformanceBenchmarkSuite(object):
 
         aggregator = BenchmarkDataAggregator(workspace, logger, 'periodic')
         aggregator.upload_metrics(rhi)
+
+
+@pytest.mark.parametrize("project", ["AutomatedTesting"])
+@pytest.mark.parametrize("launcher_platform", ['windows_generic'])
+@pytest.mark.system
+class TestMaterialEditor(object):
+
+    @pytest.mark.parametrize("cfg_args", ["-rhi=dx12", "-rhi=Vulkan"])
+    @pytest.mark.parametrize("exe_file_name", ["MaterialEditor"])
+    def test_MaterialEditorLaunch_AllRHIOptionsSucceed(
+            self, request, workspace, project, launcher_platform, generic_launcher, exe_file_name, cfg_args):
+        """
+        Tests each valid RHI option (Null RHI excluded) can be launched with the MaterialEditor.
+        Checks for the "Finished loading viewport configurtions." success message post lounch.
+        """
+        expected_lines = ["Finished loading viewport configurtions."]
+        unexpected_lines = [
+            # "Trace::Assert",
+            # "Trace::Error",
+            "Traceback (most recent call last):",
+        ]
+
+        hydra.launch_and_validate_results(
+            request,
+            TEST_DIRECTORY,
+            generic_launcher,
+            editor_script="",
+            run_python="--runpython",
+            timeout=30,
+            expected_lines=expected_lines,
+            unexpected_lines=unexpected_lines,
+            halt_on_unexpected=False,
+            null_renderer=False,
+            cfg_args=[cfg_args],
+            log_file_name="MaterialEditor.log"
+        )

AutomatedTesting/Gem/PythonTests/atom_renderer/test_Atom_MainSuite.py

@@ -303,5 +303,6 @@ class TestMaterialEditorBasicTests(object):
             expected_lines=expected_lines,
             unexpected_lines=unexpected_lines,
             halt_on_unexpected=True,
+            null_renderer=True,
             log_file_name="MaterialEditor.log",
         )