[5.0.1 L10n Admin Guide] Chinese review linguist requests to translate the contents of the {CoCo} entity

[ptinley-vt]

"Confidential Computing" is translated to "机密计算" in Chinese, so the variable "{CoCo}" should be replaced with "机密计算" thought the doc during DTP.

I tested adding the variable at the end of the file branding/locale/attributes-zh_CN.adoc and it works, even though there is another definition for CoCo: in branding/pdf/entities.adoc.
branding/locale/attributes-zh_CN.adoc obviously take precedence over branding/pdf/entities.adoc.

:CoCo: 机密计算