New Crowdin translations - zh-CN (#25202)

Co-authored-by: Crowdin Bot <support+bot@crowdin.com>

docs/zh/test_and_ci/unit_tests.md

@@ -23,7 +23,7 @@
 Tests can be run via `make tests`, after which you will find the binary in `build/px4_sitl_test/unit-MyNewUnit`.
 也可以直接通过调试器中运行。
 
-## 写一个GTest功能测试
+## Writing a GTest Functional Test {#functional-test}
 
 当测试或测试的组件依赖参数、uORB 消息、或更高级的GTest功能的时候，应当使用GTest功能测试。
 Additionally, functional tests can contain local usage of STL data structures (although be careful of platform differences between e.g. macOS and Linux).
@@ -178,3 +178,10 @@ make tests TESTFILTER=<regex filter expression>
 - `make tests TESTFILTER=unit` only run GTest unit tests
 - `make tests TESTFILTER=sitl` only run simulation tests
 - `make tests TESTFILTER=Attitude` only run the `AttitudeControl` test
+
+## Fuzz Testing
+
+Fuzz tests are a generalised form of unit test that ensures code is robust against any input.
+They are run as part of the unit tests, and also more extensively in their own testing mode.
+
+For more information see [Fuzz Tests](../test_and_ci/fuzz_tests.md).