chore: fix some typos in comments

[forcedebug]

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[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @Manishearth (or someone else) some time within the next two weeks.

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[Manishearth]

@bors r+

[bors]

:pushpin: Commit d55e5b45007569c53bb86732d05ada08a1cd8ebd has been approved by Manishearth

It is now in the queue for this repository.

[bors]

:hourglass: Testing commit d55e5b45007569c53bb86732d05ada08a1cd8ebd with merge 7eedf125a42bf7b34fc3cb1da55f13a7d56fc344...

[bors]

:broken_heart: Test failed - checks-action_test

[Manishearth]

@bors r+

[bors]

:bulb: This pull request was already approved, no need to approve it again.

• This pull request previously failed. You should add more commits to fix the bug, or use retry to trigger a build again.

[bors]

:pushpin: Commit d55e5b45007569c53bb86732d05ada08a1cd8ebd has been approved by Manishearth

It is now in the queue for this repository.

[Manishearth]

@bors retry

[bors]

:hourglass: Testing commit d55e5b45007569c53bb86732d05ada08a1cd8ebd with merge b2a7371aaad1d1a25c6c6ac83c5937a1c31ac7bc...

[bors]

:sunny: Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test Approved by: Manishearth Pushing b2a7371aaad1d1a25c6c6ac83c5937a1c31ac7bc to master...