x509: trailing bytes in DER: correct a unit test

One of the unit test was failing, because it was testing behavior
that was part of the bug. Updated the return value to the correct one
diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index 2f2137f..6b04ae3 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -755,7 +755,7 @@
 x509parse_crt:"":"":MBEDTLS_ERR_X509_INVALID_FORMAT
 
 X509 Certificate ASN1 (Correct first tag, data length does not match)
-x509parse_crt:"300000":"":MBEDTLS_ERR_X509_INVALID_FORMAT + MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+x509parse_crt:"300000":"":MBEDTLS_ERR_X509_INVALID_FORMAT + MBEDTLS_ERR_ASN1_OUT_OF_DATA
 
 X509 Certificate ASN1 (Correct first tag, no more data)
 x509parse_crt:"3000":"":MBEDTLS_ERR_X509_INVALID_FORMAT + MBEDTLS_ERR_ASN1_OUT_OF_DATA