Improve error when attempting to build with `tools=yes target=release`

(cherry picked from commit 44b68bd3b607c9c2d421ef7a5eea0565704fdf36)

SConstruct

@@ -498,8 +498,9 @@ if selected_platform in platform_list:
 
     if env["target"] == "release":
         if env["tools"]:
-            print("Tools can only be built with targets 'debug' and 'release_debug'.")
-            sys.exit(255)
+            print("ERROR: The editor can only be built with `target=debug` or `target=release_debug`.")
+            print("       Use `tools=no target=release` to build a release export template.")
+            Exit(255)
         suffix += ".opt"
         env.Append(CPPDEFINES=["NDEBUG"])