Add OpenDNS to doc-valid-idents

[avitex]

changelog: This commit adds "OpenDNS" to doc-valid-idents to avoid doc_markdown false positives.

[rust-highfive]

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) soon.

If any changes to this PR are deemed necessary, please add them as extra commits. This ensures that the reviewer can see what has changed since they last reviewed the code. Due to the way GitHub handles out-of-date commits, this should also make it reasonably obvious what issues have or haven't been addressed. Large or tricky changes may require several passes of review and changes.

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[Manishearth]

@bors r+

thanks!

[bors]

📌 Commit 51fae4e has been approved by Manishearth

[bors]

⌛ Testing commit 51fae4e with merge a5b2a56...

[bors]

💔 Test failed - checks-action_test

[giraffate]

Can you add a test? You can take a look at #5996 as an example.

[bors]

☔ The latest upstream changes (presumably #6756) made this pull request unmergeable. Please resolve the merge conflicts.

[giraffate]

I think it looks good. Thanks!

[Manishearth]

@bors r=giraffate

[bors]

📌 Commit b0d18e9 has been approved by giraffate

[bors]

⌛ Testing commit b0d18e9 with merge 76a689d...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: giraffate
Pushing 76a689d to master...