Update src/rust/src/pkcs7.rs

Co-authored-by: Copilot <[email protected]>

src/rust/src/pkcs7.rs

@@ -786,7 +786,7 @@ fn load_der_pkcs7_certificates<'p>(
             let result = load_pkcs7_certificates(py, pkcs7_decoded)?;
             if asn1::parse_single::<pkcs7::ContentInfo<'_>>(data).is_err() {
                 let warning_cls = pyo3::exceptions::PyUserWarning::type_object(py);
-                let message = cstr_from_literal!("PKCS#7 certificates could not be parsed as DER, falling back to parsing as BER. Please file an issue at https://github.com/pyca/cryptography/issues explaining how your PKCS#7 certificates was created. In the future, this may become an exception.");
+                let message = cstr_from_literal!("PKCS#7 certificates could not be parsed as DER, falling back to parsing as BER. Please file an issue at https://github.com/pyca/cryptography/issues explaining how your PKCS#7 certificates were created. In the future, this may become an exception.");
                 pyo3::PyErr::warn(py, &warning_cls, message, 1)?;
             }