Fix segfault in failing tests on Linux

Code/Tools/AssetProcessor/native/tests/platformconfiguration/platformconfigurationtests.cpp

@@ -35,12 +35,21 @@ PlatformConfigurationUnitTests::PlatformConfigurationUnitTests()
 
 void PlatformConfigurationUnitTests::SetUp()
 {
-    AZ::SettingsRegistryInterface* registry = AZ::SettingsRegistry::Get();
-    auto projectPathKey =
-        AZ::SettingsRegistryInterface::FixedValueString(AZ::SettingsRegistryMergeUtils::BootstrapSettingsRootKey) + "/project_path";
+    AZ::SettingsRegistryInterface* registry = nullptr;
+    if (!AZ::SettingsRegistry::Get())
+    {
+        AZ::SettingsRegistry::Register(&m_registry);
+        registry = &m_registry;
+    }
+    else
+    {
+        registry = AZ::SettingsRegistry::Get();
+    }
+    auto projectPathKey = AZ::SettingsRegistryInterface::FixedValueString(AZ::SettingsRegistryMergeUtils::BootstrapSettingsRootKey)
+        + "/project_path";
     registry->Set(projectPathKey, "AutomatedTesting");
     AZ::SettingsRegistryMergeUtils::MergeSettingsToRegistry_AddRuntimeFilePaths(*registry);
-
+    
     using namespace AssetProcessor;
     m_qApp = new QCoreApplication(m_argc, m_argv);
     AssetProcessorTest::SetUp();

Code/Tools/AssetProcessor/native/tests/platformconfiguration/platformconfigurationtests.h

@@ -13,6 +13,7 @@
 #pragma once
 
 #include <AzTest/AzTest.h>
+#include <AzCore/Settings/SettingsRegistryImpl.h>
 #include <QCoreApplication>
 #include "native/tests/AssetProcessorTest.h"
 #include "native/unittests/UnitTestRunner.h"
@@ -37,6 +38,6 @@ private:
     int         m_argc;
     char**      m_argv;
     QCoreApplication* m_qApp;
-    
+    AZ::SettingsRegistryImpl m_registry;    
 };