[doc] remove useless tags to make the doc render properly

[alex4506]

Description

Some useless span tags make the markdown render failed under Docusaurus v2.4.1
, need remove them

Test Plan

[davidiw]

unfortunately these are used for redirects, so we would need to find some other means of placing an anchor.

thanks for the improvement though, it does look better....

[github-actions]

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