tests(helpers): support ldoc generation (#13636)

KAG-5333, support ldoc generation.
- edit `config.ld`, add directory `./details` and `merge=true`
- add `@module` header for separated test modules

spec/config.ld

@@ -2,10 +2,11 @@ project='Kong test helpers'
 title='Kong test framework'
 description='Test helper functions for Kong (integration) testing'
 format='markdown'
-file={'./helpers.lua','./helpers'}
+file={'./helpers.lua','./helpers','./details'}
 dir='docs'
 readme='README.md'
 sort=true
 sort_modules=true
 style='./'
 no_space_before_args=true
+merge=true

spec/details/dns.lua

@@ -1,3 +1,11 @@
+------------------------------------------------------------------
+-- Collection of utilities to help testing Kong features and plugins.
+--
+-- @copyright Copyright 2016-2022 Kong Inc. All rights reserved.
+-- @license [Apache 2.0](https://opensource.org/licenses/Apache-2.0)
+-- @module spec.helpers
+
+
 local cjson = require("cjson.safe")
 
 

spec/details/misc.lua

@@ -1,3 +1,11 @@
+------------------------------------------------------------------
+-- Collection of utilities to help testing Kong features and plugins.
+--
+-- @copyright Copyright 2016-2022 Kong Inc. All rights reserved.
+-- @license [Apache 2.0](https://opensource.org/licenses/Apache-2.0)
+-- @module spec.helpers
+
+
 -- miscellaneous
 
 

spec/details/shell.lua

@@ -1,3 +1,11 @@
+------------------------------------------------------------------
+-- Collection of utilities to help testing Kong features and plugins.
+--
+-- @copyright Copyright 2016-2022 Kong Inc. All rights reserved.
+-- @license [Apache 2.0](https://opensource.org/licenses/Apache-2.0)
+-- @module spec.helpers
+
+
 local shell = require("resty.shell")
 local conf_loader = require("kong.conf_loader")
 local strip = require("kong.tools.string").strip