Fix antsibull-docs error if unexpected plugin type is documented (#404)

* Fix anstibull error if expected diff plugin list

* F it

* clog

* Update changelogs/fragments/404_not_found.yml

Co-authored-by: Felix Fontein <felix@fontein.de>

changelogs/fragments/404_not_found.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - anstibull-docs will no longer traceback when it tries to process plugins not found in its own constant but are available in ansible-core (https://github.com/ansible-community/antsibull/pull/404).

src/antsibull/docs_parsing/ansible_internal.py

@@ -8,6 +8,7 @@
 import tempfile
 import typing as t
 
+from ..constants import DOCUMENTABLE_PLUGINS
 from ..logging import log
 from ..utils.get_pkg_data import get_antsibull_data
 from ..vendored.json_utils import _filter_non_json_lines
@@ -65,6 +66,10 @@ async def get_ansible_plugin_info(venv: t.Union['VenvRunner', 'FakeVenvRunner'],
 
     plugin_map = {}
     for plugin_type, plugins in result['plugins'].items():
+        if plugin_type not in DOCUMENTABLE_PLUGINS:
+            # avoid keyerrors down the line when we cannot match types
+            flog.debug(f'Skipping unknown plugin type: {plugin_type}')
+            continue
         plugin_map[plugin_type] = {}
         for plugin_name, plugin_data in plugins.items():
             if '.' not in plugin_name: