Fix AssetBuilders when project-path has a trailing slash (#1345)

* Fixes issues with project paths w/ trailing slash

When launching AP with a --project-path that has a trailing slash, the
AssetBuilders would get that slash instead of a normalized version.
This would mess up the params sent to AssetBuilders.

* Missed a variable name replacement

* Addresses feedback on code style guidelines

Removed 'auto' keyword in favor of explicit types.

Code/Tools/AssetProcessor/native/utilities/BuilderManager.cpp

@@ -12,6 +12,7 @@
 
 #include "BuilderManager.h"
 #include <AzCore/std/smart_ptr/make_shared.h>
+#include <AzCore/Utils/Utils.h>
 
 #include <AzFramework/API/ApplicationAPI.h>
 #include <native/connection/connectionManager.h>
@@ -186,10 +187,9 @@ namespace AssetProcessor
         QDir projectCacheRoot;
         AssetUtilities::ComputeProjectCacheRoot(projectCacheRoot);
 
-        QString gameName = AssetUtilities::ComputeProjectName();
-        QString projectPath = AssetUtilities::ComputeProjectPath();
-        QDir engineRoot;
-        AssetUtilities::ComputeEngineRoot(engineRoot);
+        AZ::SettingsRegistryInterface::FixedValueString projectName = AZ::Utils::GetProjectName();
+        AZ::IO::FixedMaxPathString projectPath = AZ::Utils::GetProjectPath();
+        AZ::IO::FixedMaxPathString enginePath = AZ::Utils::GetEnginePath();
 
         int portNumber = 0;
         ApplicationServerBus::BroadcastResult(portNumber, &ApplicationServerBus::Events::GetServerListeningPort);
@@ -197,14 +197,14 @@ namespace AssetProcessor
         AZStd::string params;
 #if !AZ_TRAIT_OS_PLATFORM_APPLE && !AZ_TRAIT_OS_USE_WINDOWS_FILE_PATHS
         params = AZStd::string::format(
-            R"(-task=%s -id="%s" -project-name="%s" -project-cache-path="%s" -project-path="%s" -engine-path="%s" -port %d)", task,
-            builderGuid.c_str(), gameName.toUtf8().constData(), projectCacheRoot.absolutePath().toUtf8().constData(),
-            projectPath.toUtf8().constData(), engineRoot.absolutePath().toUtf8().constData(), portNumber);
+            R"(-task=%s -id="%s" -project-name="%s" -project-cache-path="%s" -project-path="%s" -engine-path="%s" -port %d)",
+            task, builderGuid.c_str(), projectName.c_str(), projectCacheRoot.absolutePath().toUtf8().constData(),
+            projectPath.c_str(), enginePath.c_str(), portNumber);
 #else
         params = AZStd::string::format(
             R"(-task=%s -id="%s" -project-name="\"%s\"" -project-cache-path="\"%s\"" -project-path="\"%s\"" -engine-path="\"%s\"" -port %d)",
-            task, builderGuid.c_str(), gameName.toUtf8().constData(), projectCacheRoot.absolutePath().toUtf8().constData(),
-            projectPath.toUtf8().constData(), engineRoot.absolutePath().toUtf8().constData(), portNumber);
+            task, builderGuid.c_str(), projectName.c_str(), projectCacheRoot.absolutePath().toUtf8().constData(),
+            projectPath.c_str(), enginePath.c_str(), portNumber);
 #endif // !AZ_TRAIT_OS_PLATFORM_APPLE && !AZ_TRAIT_OS_USE_WINDOWS_FILE_PATHS
 
         if (moduleFilePath && moduleFilePath[0])