test: cover message hook list entries that are not dicts

Exercises the process_commit_message branch that skips non-dict items so
Codecov patch coverage meets the project threshold.

Made-with: Cursor

Author: bearomorphism

tests/test_changelog.py

@@ -1468,6 +1468,32 @@ def changelog_message_builder_hook(message: dict, commit: git.GitCommit):
         assert f"Message #{idx}" in result
 
 
+def test_changelog_message_builder_hook_skips_non_dict_entries(
+    gitcommits, tags, any_changelog_format: ChangelogFormat
+):
+    """Non-dict elements in a list returned by the hook are skipped."""
+
+    def changelog_message_builder_hook(message: dict, commit: git.GitCommit):
+        second = message.copy()
+        second["message"] = "second entry"
+        return [message, "not-a-dict-commit", second]
+
+    parser = ConventionalCommitsCz.commit_parser
+    changelog_pattern = ConventionalCommitsCz.changelog_pattern
+    loader = ConventionalCommitsCz.template_loader
+    template = any_changelog_format.template
+    tree = changelog.generate_tree_from_commits(
+        gitcommits,
+        tags,
+        parser,
+        changelog_pattern,
+        changelog_message_builder_hook=changelog_message_builder_hook,
+    )
+    result = changelog.render_changelog(tree, loader, template)
+
+    assert "second entry" in result
+
+
 def test_changelog_message_builder_hook_can_access_and_modify_change_type(
     gitcommits, tags, any_changelog_format: ChangelogFormat
 ):