docs/zh_CN: link development-process into process index

Then this doc could be find via process index.
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Harry Wei <harryxiyou@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/translations/zh_CN/process/index.rst

@@ -25,6 +25,7 @@
    howto
    submitting-patches
    coding-style
+   development-process
    email-clients
 
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