refactor: use truthy values in dictionaries used as hashsets (#422)

Author: Qubus0

addons/mod_loader/internal/hooks.gd

@@ -18,7 +18,7 @@ static func add_hook(mod_callable: Callable, script_path: String, method_name: S
 		% [script_path, "before" if is_before else "after", method_name ], LOG_NAME
 	)
 	if not ModLoaderStore.hooked_script_paths.has(script_path):
-		ModLoaderStore.hooked_script_paths[script_path] = null
+		ModLoaderStore.hooked_script_paths[script_path] = true
 
 
 static func call_hooks(self_object: Object, args: Array, hook_hash:int) -> void:

addons/mod_loader/internal/mod_hook_preprocessor.gd

@@ -368,10 +368,10 @@ static func collect_getters_and_setters(text: String, regex_getter_setter: RegEx
 	for mat in regex_getter_setter.search_all(text):
 		if mat.get_string(1).is_empty() or mat.get_string(1).contains("#"):
 			continue
-		result[mat.get_string(2)] = null
+		result[mat.get_string(2)] = true
 
 		if mat.get_string(3).is_empty() or mat.get_string(3).contains("#"):
 			continue
-		result[mat.get_string(4)] = null
+		result[mat.get_string(4)] = true
 
 	return result

addons/mod_loader/mod_loader_store.gd

@@ -45,7 +45,7 @@ var modding_hooks := {}
 
 # Example:
 # var hooked_script_paths := {
-# 	"res://game/game.gd": null,
+# 	"res://game/game.gd": true,
 # }
 var hooked_script_paths := {}