[webidl] Fix a typo in editorial note for @@toStringTag (#39)

All `@@toStringTag` instances, short of `Symbol.toStringTag` (where it's exposed as a public API), are configurable in ES6 --- although not everyone is happy about that. It's likely to stay that way
You can view, comment on, or merge this pull request online at:

  https://github.com/heycam/webidl/pull/39

-- Commit Summary --

  * Fix a typo in editorial note for @@toStringTag

-- File Changes --

    M index.xml (4)

-- Patch Links --

https://github.com/heycam/webidl/pull/39.patch
https://github.com/heycam/webidl/pull/39.diff

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Reply to this email directly or view it on GitHub:
https://github.com/heycam/webidl/pull/39