Add lists filtering APIs to doxygen group. (rapidsai#11336)

This PR follows up on rapidsai#11149 to add the lists filtering (stream compaction) APIs to a doxygen group. The previous doxygen group `lists_drop_duplicates` is empty after rapidsai#11326.

Authors:
  - Bradley Dice (https://github.com/bdice)

Approvers:
  - David Wendt (https://github.com/davidwendt)
  - Vukasin Milovanovic (https://github.com/vuule)

URL: rapidsai#11336

cpp/include/cudf/lists/stream_compaction.hpp

@@ -23,6 +23,12 @@
 
 namespace cudf::lists {
 
+/**
+ * @addtogroup lists_filtering
+ * @{
+ * @file
+ */
+
 /**
  * @brief Filters elements in each row of `input` LIST column using `boolean_mask`
  * LIST of booleans as a mask.
@@ -81,4 +87,6 @@ std::unique_ptr<column> distinct(
   nan_equality nans_equal             = nan_equality::ALL_EQUAL,
   rmm::mr::device_memory_resource* mr = rmm::mr::get_current_device_resource());
 
+/** @} */  // end of group
+
 }  // namespace cudf::lists

cpp/include/doxygen_groups.h

@@ -150,7 +150,7 @@
  *   @defgroup lists_contains Searching
  *   @defgroup lists_gather Gathering
  *   @defgroup lists_elements Counting
- *   @defgroup lists_drop_duplicates Filtering
+ *   @defgroup lists_filtering Filtering
  *   @defgroup lists_sort Sorting
  * @}
  * @defgroup nvtext_apis NVText