Prevent package finders from processing the wrapped directory (#136)

* Prevent package finders from processing the wrapped directory

* Use pathlib touch in COLCON_IGNORE create

rosdoc2/verbs/build/builders/sphinx_builder.py

@@ -16,6 +16,7 @@
 import json
 import logging
 import os
+from pathlib import Path
 import shutil
 import subprocess
 
@@ -419,6 +420,7 @@ def build(self, *, doc_build_folder, output_staging_directory):
         wrapped_sphinx_directory = os.path.abspath(
             os.path.join(doc_build_folder, 'wrapped_sphinx_directory'))
         os.makedirs(wrapped_sphinx_directory, exist_ok=True)
+        Path(wrapped_sphinx_directory).joinpath('COLCON_IGNORE').touch()
 
         # Generate rst documents for interfaces
         interface_counts = generate_interface_docs(