Fix the Boring tests following the SSLfatal() changes

An error reason code has changed for one of the boring tests, so
ossl_config.json needed an update to take account of it.

[extended tests]
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4778)

test/ossl_shim/ossl_config.json

@@ -277,7 +277,7 @@
         ":BAD_DH_P_LENGTH:":"dh key too small",
         ":PEER_DID_NOT_RETURN_A_CERTIFICATE:":"peer did not return a certificate",
         ":UNSUPPORTED_PROTOCOL:":"unsupported protocol",
-        ":PARSE_TLSEXT:":"parse tlsext",
+        ":PARSE_TLSEXT:":"bad extension",
         ":BAD_SRTP_PROTECTION_PROFILE_LIST:":"bad srtp protection profile list",
         ":OLD_SESSION_VERSION_NOT_RETURNED:":"ssl session version mismatch",
         ":RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION:":"inconsistent extms",