enable offline search with Lunr

- Disables the GCSE (which pointed to Docs's docs anyways).
- Enable the Lunr offline search.

Author: alexrashed

config.toml

@@ -130,13 +130,13 @@ github_project_repo = "https://github.com/localstack/localstack"
 github_branch= "main"
 
 # Google Custom Search Engine ID. Remove or comment out to disable search.
-gcs_engine_id = "d72aa9b2712488cc3"
+# gcs_engine_id = "d72aa9b2712488cc3"
 
 # Enable Algolia DocSearch
 algolia_docsearch = false
 
 # Enable Lunr.js offline search
-offlineSearch = false
+offlineSearch = true
 
 # Enable syntax highlighting and copy buttons on code blocks with Prism
 prism_syntax_highlighting = false