Merge pull request #505 from sharplab/fix-typos

Fix typo.

index.bs

@@ -1550,7 +1550,7 @@ input parameters:
 - The user account's {{PublicKeyCredentialUserEntity}}.
 - A sequence of pairs of {{PublicKeyCredentialType}} and cryptographic algorithms (a dictionary type) requested by the [=[RP]=],
     where the cryptographic algorithms are normalized as per the procedure in
-    [[WebCryptoAPI#algorithm-normalization-normalize-an-algorithm]]. This sequence is is ordered from most preferred to least
+    [[WebCryptoAPI#algorithm-normalization-normalize-an-algorithm]]. This sequence is ordered from most preferred to least
     preferred. The platform makes a best-effort to create the most preferred credential that it can.
 - An optional list of {{PublicKeyCredentialDescriptor}} objects provided by the [=[RP]=] with the intention that, if any of
     these are known to the authenticator, it should not create a new credential.
@@ -1776,7 +1776,7 @@ template:
     the [=public key credential=] to be attested, the [=authenticator data=] structure containing the <dfn>authenticator data
     for the attestation</dfn>, and the [=hash of the serialized client data=].
 
-- <dfn>Verification procedurs</dfn>:
+- <dfn>Verification procedures</dfn>:
     The procedure for verifying an [=attestation statement=], which takes as inputs the [=authenticator data=] structure
     containing the <dfn>authenticator data claimed to have been used for the attestation</dfn> and the [=hash of the serialized
     client data=], and returns either: