docs: add libbsd-dev to linux host requirements list

docs/en/api-guides/inc/linux-host-requirements.rst

@@ -0,0 +1,3 @@
+- Installed IDF including all IDF requirements
+- CMock requirements (``Ruby``)
+- System package requirements (``libbsd``, ``libbsd-dev``)

docs/en/api-guides/linux-host-testing.rst

@@ -60,8 +60,6 @@ The :component_file:`NVS page unit test <nvs_flash/host_test/nvs_page_test/main/
 Requirements
 ^^^^^^^^^^^^
 
-- Installed IDF including all IDF requirements
-- CMock requirements (``Ruby``)
-- ``libbsd``
+.. include:: inc/linux-host-requirements.rst
 
 The host tests have been tested on Ubuntu 20.04 with ``GCC`` version 9 and 10.

docs/en/api-guides/unit-tests.rst

@@ -300,12 +300,9 @@ Refer to :component_file:`cmock/CMock/docs/CMock_Summary.md` for more details on
 
 Requirements
 ^^^^^^^^^^^^
-The following requirements are necessary to generate the mocks:
+The Linux target is the only target where mocking currently works. The following requirements are necessary to generate the mocks:
 
-.. list::
-    - Installed ESP-IDF with all its requirements
-    - ``ruby``
-    - On the Linux target, which is the only target where mocking currently works, ``libbsd`` is required, too
+.. include:: inc/linux-host-requirements.rst
 
 Mock a Component
 ^^^^^^^^^^^^^^^^

docs/zh_CN/api-guides/inc/linux-host-requirements.rst

@@ -0,0 +1 @@
+.. include:: ../../en/api-guides/inc/linux-host-requirements.rst