Fix crawling of cards without descriptions

CHANGELOG.md

@@ -25,6 +25,7 @@ ambiguous situations.
 ### Fixed
 - Crawling of courses with the timeline view as the default tab
 - Crawling of file and custom opencast cards
+- Crawling of button cards without descriptions
 
 ## 3.4.3 - 2022-11-29
 

PFERD/crawl/ilias/kit_ilias_html.py

@@ -708,7 +708,11 @@ class IliasPage:
                 "div",
                 attrs={"class": lambda x: x and "caption" in x},
             )
-            description = caption_parent.find_next_sibling("div").getText().strip()
+            caption_container = caption_parent.find_next_sibling("div")
+            if caption_container:
+                description = caption_container.getText().strip()
+            else:
+                description = None
 
             if not type:
                 _unexpected_html_warning()