Update launcher.md to wrap code blocks (#1076)

Wrap code blocks in `launcher` doc page

using https://github.com/huggingface/doc-builder/pull/420


https://moon-ci-docs.huggingface.co/docs/text-generation-inference/pr_1076/en/basic_tutorials/launcher

<img width="800" alt="image"
src="https://github.com/huggingface/text-generation-inference/assets/11827707/cb240198-411f-4d22-9f6e-8f70f2c6dcab">

docs/source/basic_tutorials/launcher.md

 # Text-generation-launcher arguments
 
+<!-- WRAP CODE BLOCKS -->
+
 ```
 Text Generation Launcher
 

update_doc.py

@@ -11,7 +11,8 @@ def main():
     output = subprocess.check_output(["text-generation-launcher", "--help"]).decode(
         "utf-8"
     )
-    final_doc = f"# Text-generation-launcher arguments\n\n```\n{output}\n```"
+    wrap_code_blocks_flag = "<!-- WRAP CODE BLOCKS -->"
+    final_doc = f"# Text-generation-launcher arguments\n\n{wrap_code_blocks_flag}\n\n```\n{output}\n```"
 
     filename = "docs/source/basic_tutorials/launcher.md"
     if args.check: