docs: fix typo in readme

README.md

@@ -15,7 +15,7 @@ This crate uses the [Double Submit Cookie Pattern][owasp-double-submit] to mitig
 
 ### How it works
 
-- **Secret key**: You provide a **secret key** used to sign CSRF tokens. This token is secured by [secstr][crate-secstr] and only
+- **Secret key**: You provide a **secret key** used to sign CSRF tokens. This secret is secured by [secstr][crate-secstr] and only
 in memory as plaintext during the signing and validating processes.
 For more information on managing your secret key, see [OWASP's Cryptographic Storage Cheat Sheet][owasp-cryptographic-storage]).
 - **Token creation**: