DOCSP-45311: Remove deprecated utf8 types

source/upgrade.txt

@@ -151,6 +151,17 @@ The v4.0 driver introduces the following breaking changes to the API:
   library equivalents. For context, see the :ref:`Build System Breaking Changes
   <version-4.0-build-system-breaking>` section.
 
+- Removes the following deprecated ``utf8`` types and methods that have ``string`` equivalents:
+
+  - ``k_utf8`` from the ``bsoncxx::v_noabi::type`` class. Instead, use ``k_string``.
+  - ``b_utf8`` from the ``bsoncxx::v_noabi::types`` class. Instead, use ``b_string``.
+  - ``get_utf8()`` from the ``bsoncxx::v_noabi::document::element``, ``bsoncxx::v_noabi::array::element``,
+    and ``bsoncxx::v_noabi::types::bson_value::view`` classes. Instead, use ``get_string()``.
+  - ``k_cannot_append_utf8`` from the ``bsoncxx::v_noabi::exception::error_code`` class.
+    Instead, use ``k_cannot_append_string``.
+  - ``k_need_element_type_k_utf8`` from the ``bsoncxx::v_noabi::exception::error_code`` class.
+    Instead, use ``k_need_element_type_k_string``.
+
 ABI Breaking Changes in v4.0
 ````````````````````````````