docs: Fix in nullifier secrets doc (#3167)

Credit to @skeletor-spaceman for the find

Co-authored-by: Skeletor Spaceman <skeletorspaceman@gmail.com>

docs/docs/concepts/foundation/accounts/keys.md

@@ -82,7 +82,7 @@ Note that any accounts you own that have been added to the PXE are automatically
 
 In addition to deriving encryption keys, the privacy master key is used for deriving nullifier secrets. Whenever a private note is consumed, a nullifier deterministically derived from it is emitted. This mechanisms prevents double-spends, since nullifiers are checked by the protocol to be unique. Now, in order to preserve privacy, a third party should not be able to link a note commitment to its nullifier - this link is enforced by the note implementation. Therefore, calculating the nullifier for a note requires a secret from its owner.
 
-An application in Aztec.nr can request a nullifier from the current user for computing the nullifier of a note via the `get_secret_key` oracle call:
+An application in Aztec.nr can request a secret from the current user for computing the nullifier of a note via the `get_secret_key` oracle call:
 
 #include_code nullifier /yarn-project/aztec-nr/value-note/src/value_note.nr rust