Make prefab system enabled as default for automated tests (#5670)

* Make prefab system enabled as default for automated tests

Signed-off-by: chiyenteng <82238204+chiyenteng@users.noreply.github.com>

* Modify auto tests after preventing regset saved into disk after editor main window closed

Signed-off-by: chiyenteng <82238204+chiyenteng@users.noreply.github.com>

* Uncomment xfail

Signed-off-by: chiyenteng <82238204+chiyenteng@users.noreply.github.com>

* Use --regset for editor tests

Signed-off-by: chiyenteng <82238204+chiyenteng@users.noreply.github.com>

AutomatedTesting/Gem/PythonTests/Atom/TestSuite_Main.py

@@ -13,6 +13,8 @@ from ly_test_tools.o3de.editor_test import EditorSharedTest, EditorTestSuite
 @pytest.mark.parametrize("launcher_platform", ['windows_editor'])
 class TestAutomation(EditorTestSuite):
 
+    enable_prefab_system = False
+
     @pytest.mark.test_case_id("C36525657")
     class AtomEditorComponents_BloomAdded(EditorSharedTest):
         from Atom.tests import hydra_AtomEditorComponents_BloomAdded as test_module

AutomatedTesting/Gem/PythonTests/Atom/TestSuite_Main_GPU.py

@@ -104,6 +104,7 @@ class TestAllComponentsIndepthTests(object):
             halt_on_unexpected=True,
             cfg_args=[level],
             null_renderer=False,
+            enable_prefab_system=False,
         )
 
         similarity_threshold = 0.99
@@ -158,6 +159,7 @@ class TestAllComponentsIndepthTests(object):
             halt_on_unexpected=True,
             cfg_args=[level],
             null_renderer=False,
+            enable_prefab_system=False,
         )
 
         similarity_threshold = 0.99
@@ -205,6 +207,7 @@ class TestPerformanceBenchmarkSuite(object):
             halt_on_unexpected=True,
             cfg_args=[level],
             null_renderer=False,
+            enable_prefab_system=False,
         )
 
         aggregator = BenchmarkDataAggregator(workspace, logger, 'periodic')
@@ -242,5 +245,6 @@ class TestMaterialEditor(object):
             halt_on_unexpected=False,
             null_renderer=False,
             cfg_args=[cfg_args],
-            log_file_name="MaterialEditor.log"
+            log_file_name="MaterialEditor.log",
+            enable_prefab_system=False,
         )

AutomatedTesting/Gem/PythonTests/Atom/TestSuite_Main_GPU_Optimized.py

@@ -23,6 +23,8 @@ class TestAutomation(EditorTestSuite):
     # Remove -autotest_mode from global_extra_cmdline_args since we need rendering for these tests.
     global_extra_cmdline_args = ["-BatchMode"]  # Default is ["-BatchMode", "-autotest_mode"]
 
+    enable_prefab_system = False
+
     @pytest.mark.test_case_id("C34603773")
     class AtomGPU_BasicLevelSetup_SetsUpLevel(EditorSharedTest):
         use_null_renderer = False  # Default is True

AutomatedTesting/Gem/PythonTests/Atom/TestSuite_Sandbox.py

@@ -85,6 +85,7 @@ class TestAtomEditorComponentsMain(object):
             halt_on_unexpected=True,
             null_renderer=True,
             cfg_args=cfg_args,
+            enable_prefab_system=False,
         )
 
 
@@ -155,5 +156,6 @@ class TestMaterialEditorBasicTests(object):
             halt_on_unexpected=True,
             null_renderer=True,
             log_file_name="MaterialEditor.log",
+            enable_prefab_system=False,
         )