Add support for `[TOC]` to generate a table of contents in Markdown

Additional information from issue https://gitlab.com/gitlab-org/gitlab-ce/issues/64358 and #21901 (closed)

Currently, it is possible to generate a Table of Contents in Markdown by adding the [[_TOC_]] tag. This was added in Issue gitlab-ce#2494 and !24196 (merged). Would it be possible to extend this to support using

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to add a Table of Contents as well? As noted in the forum thread below, some Markdown editors such as stackedit.io and Typora interpret

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as a ToC rather than [[_TOC_]]. I also have my repository's wiki mirrored on Bitbucket and I found that their software also recognises

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but not [[_TOC_]]. Thanks.

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git user

sth.....

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Links / references

• https://forum.gitlab.com/t/table-of-contents-toc-in-markdown-wiki-and-general/9394
• https://confluence.atlassian.com/bitbucket/add-a-table-of-contents-to-a-wiki-221451163.html
• https://support.typora.io/Markdown-Reference/#table-of-contents-toc