Add "Registry" folders as scan folders (#4583)

* Add "Registry" folders as scan folders

For projects, Gems, and Engine, add the "Registry" folder as scan
folders.

Signed-off-by: amzn-phist <52085794+amzn-phist@users.noreply.github.com>

* Change params for adding scan folder

Also add trailing newlines to setreg files.

Signed-off-by: amzn-phist <52085794+amzn-phist@users.noreply.github.com>

* Adjust the priority order for project templates

Scan folder orders were way too high, they should be very low to become
highest priority order.

Signed-off-by: amzn-phist <52085794+amzn-phist@users.noreply.github.com>

* Removes change of default assets folder to Assets

Need to revert this change so it can be done separately.
Renamed the scan folder to 'Project/Assets' to prep for Assets folder
change later on.

Signed-off-by: amzn-phist <52085794+amzn-phist@users.noreply.github.com>

* Update platform configuration test to pass

Adjusted expectation of scan folder count from 1 to 2 per Gem for
'Assets' and 'Registry' now.

Signed-off-by: amzn-phist <52085794+amzn-phist@users.noreply.github.com>

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

@@ -1582,6 +1582,24 @@ namespace AssetProcessor
                     gemOrder,
                     /*scanFolderId*/ 0,
                     /*canSaveNewAssets*/ true)); // Users can create assets like slices in Gem asset folders.
+
+                // Now add another scan folder on Gem/GemName/Registry...
+                gemFolder = gemDir.absoluteFilePath(AzFramework::GemInfo::GetGemRegistryFolder());
+                gemFolder = AssetUtilities::NormalizeDirectoryPath(gemFolder);
+
+                assetBrowserDisplayName = AzFramework::GemInfo::GetGemRegistryFolder();
+                portableKey = QString("gemregistry-%1").arg(gemNameAsUuid);
+                gemOrder++;
+
+                AZ_TracePrintf(AssetProcessor::DebugChannel, "Adding GEM registry folder for monitoring / scanning: %s.\n", gemFolder.toUtf8().data());
+                AddScanFolder(ScanFolderInfo(
+                    gemFolder,
+                    assetBrowserDisplayName,
+                    portableKey,
+                    isRoot,
+                    isRecursive,
+                    platforms,
+                    gemOrder));
             }
         }
     }