Add ZEN_GA_DISABLE_PGO environment variable to disable PGO and update codesign script for verbose output

configs/macos/mozconfig

@@ -7,8 +7,12 @@ export MOZ_MACBUNDLE_ID=${appId}
 export MOZ_MACBUNDLE_NAME="Zen Browser.app"
 
 if test "$ZEN_RELEASE"; then
-  export MOZ_PGO=1
-  ac_add_options MOZ_PGO=1
+  if test "$ZEN_GA_DISABLE_PGO"; then
+    export ZEN_DUMMY=1
+  else
+    export MOZ_PGO=1
+    ac_add_options MOZ_PGO=1
+  fi
 fi
 
 if test "$SURFER_COMPAT" = "x86_64"; then