[webauthn] Merged Pull Request: fix "present" link errors along with a couple others

equalsJeffH has just merged equalsJeffH's pull request 1433 for https://github.com/w3c/webauthn:

== fix "present" link errors along with a couple others ==
this is editorial clean up: fixes #1397 along with a couple other linking errors that were showing up when building the spec.


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<a href="https://pr-preview.s3.amazonaws.com/w3c/webauthn/pull/1433.html" title="Last updated on Jun 5, 2020, 3:36 PM UTC (1d1145f)">Preview</a> | <a href="https://pr-preview.s3.amazonaws.com/w3c/webauthn/1433/7f541a2...1d1145f.html" title="Last updated on Jun 5, 2020, 3:36 PM UTC (1d1145f)">Diff</a>

See https://github.com/w3c/webauthn/pull/1433