[streams] Fix markup (#399)

I didn’t try to figure out how to build the specification.
You can view, comment on, or merge this pull request online at:

  https://github.com/whatwg/streams/pull/399

-- Commit Summary --

  * Fix markup

-- File Changes --

    M index.bs (12)

-- Patch Links --

https://github.com/whatwg/streams/pull/399.patch
https://github.com/whatwg/streams/pull/399.diff

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/streams/pull/399