You no longer need Yahoo verification. It just points you at Bing to do it.
Google is now much easier. Just get a Google Analytics id and that is good enough.
No everyone has the new async Google Analytics snippet.
Still would be good to nix the Yahoo pages.
Google encourages use verification through DNS (no longer possible to do with html file) and it is also possible to do for Bing
This should get rid of yahoo..
Not sure what is needed for google, but it seems to work as is no matter how easy it is via other means.
EDIT: Must remember to remove it project page https://www.drupal.org/project/site_verify too
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