colcon returns with success when extension loading fails

[christianrauch]

When an extension throws an exception during loading, a backtrace is shown but colcon continues:

colcon-core/colcon_core/extension_point.py

Lines 165 to 176 in 15ed7d6

	try:
	extension_type = load_extension_point(name, value, group)
	except RuntimeError:
	continue
	except Exception as e: # noqa: F841
	# catch exceptions raised when loading entry point
	exc = traceback.format_exc()
	logger.error(
	'Exception loading extension '
	f"'{group}.{name}': {e}\n{exc}")
	# skip failing entry point, continue with next one
	continue

That means, if an extension fails to load, colcon will return with exit code 0, indicating success. For automation, it would be more useful if colcon returns an exit code indicating an error.