Revert "fix: support overwrite when merge config. (#1394)"

This reverts commit 7056741.

Sorry for the noise but I'm a lil confused about this new option...? Like idk if
the performance difference between these two is even that big, and maybe it's
not actually working as expected?

lua/modules/configs/ui/edgy.lua

@@ -91,5 +91,5 @@ return function()
 				filter = trouble_filter("right"),
 			},
 		},
-	}, false, nil, true)
+	})
 end

lua/modules/utils/init.lua

@@ -297,8 +297,7 @@ end
 ---@param opts nil|table @The default config to be merged with
 ---@param vim_plugin? boolean @If this plugin is written in vimscript or not
 ---@param setup_callback? function @Add new callback if the plugin needs unusual setup function
----@param overwrite? boolean @If load user table-type config by overwriting
-function M.load_plugin(plugin_name, opts, vim_plugin, setup_callback, overwrite)
+function M.load_plugin(plugin_name, opts, vim_plugin, setup_callback)
 	vim_plugin = vim_plugin or false
 
 	-- Get the file name of the default config
@@ -331,11 +330,7 @@ function M.load_plugin(plugin_name, opts, vim_plugin, setup_callback, overwrite)
 			if ok then
 				-- Extend base config if the returned user config is a table
 				if type(user_config) == "table" then
-					if overwrite == true then
-						opts = vim.tbl_deep_extend("force", opts, user_config)
-					else
-						opts = tbl_recursive_merge(opts, user_config)
-					end
+					opts = tbl_recursive_merge(opts, user_config)
 					setup_callback(opts)
 				-- Replace base config if the returned user config is a function
 				elseif type(user_config) == "function" then