docs/zh_CN: Add dev-tools/kcov Chinese translation

Translate dev-tools/kcov into Chinese and add it in
dev-tools/zh_CN/index.rst.
Signed-off-by: Haoyang Liu <tttturtleruss@hust.edu.cn>
Reviewed-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Alex Shi <alexs@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240421142021.19504-1-tttturtleruss@hust.edu.cn

Documentation/translations/zh_CN/dev-tools/index.rst

@@ -22,6 +22,7 @@ Documentation/translations/zh_CN/dev-tools/testing-overview.rst
    sparse
    gcov
    kasan
+   kcov
    ubsan
    kmemleak
    gdb-kernel-debugging
@@ -29,7 +30,6 @@ Documentation/translations/zh_CN/dev-tools/testing-overview.rst
 Todolist:
 
  - coccinelle
- - kcov
  - kcsan
  - kfence
  - kgdb