cleanup: run XCode code analysis

enable ARC in CMakelist.txt
fix small potentials leaks across the client

Refs #75600

Change-Id: I72ba17e6daed393abdf38653f45c040bd3427ead
diff --git a/src/GeneralPrefsVC.h b/src/GeneralPrefsVC.h
index ef059ae..cffd689 100644
--- a/src/GeneralPrefsVC.h
+++ b/src/GeneralPrefsVC.h
@@ -32,10 +32,7 @@
 
 #import <Cocoa/Cocoa.h>
 
-@interface GeneralPrefsVC : NSViewController {
-
-    NSTextField *historyChangedLabel;
-}
+@interface GeneralPrefsVC : NSViewController
 
 @end