[fetch] added a couple missing backticks (#177)

I found a couple missing backticks in a HTTP-network Fetch step, so I added them.
You can view, comment on, or merge this pull request online at:

  https://github.com/whatwg/fetch/pull/177

-- Commit Summary --

  * added a couple missing backticks

-- File Changes --

    M Overview.src.html (4)

-- Patch Links --

https://github.com/whatwg/fetch/pull/177.patch
https://github.com/whatwg/fetch/pull/177.diff

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/pull/177