docs: update README about usages

README.md

@@ -24,13 +24,13 @@ local lspconfig = require("lspconfig")
 
 lspconfig.github_actions.setup({
   --@see https://github.com/actions/languageservices/blob/main/languageserver/src/initializationOptions.ts#L4-L31
-  init_params = {
-    sessionToken = "Your GitHub PAT (needed scopes is repo & workflow)",
-    logLevel = 3 -- Debug: 0, Info: 1, Warn: 2, Error: 3, Default: nil
-  }
+  init_params = {}
 })
 ```
 
+> [!CAUTION]
+> At this time, we have not investigated how to obtain the `settionToken` and `repos` to be passed to `init_params`, so if you use the default values, auto-completion will not work for global `env` and `vars`, and for custom action `args` etc.
+
 ## Credits
 
 - [@actions/languageserver](https://github.com/actions/languageservices/tree/main/languageserver)