We found this while testing cert auth for rsync-ssl with openssl cli as
backend. rsync-ssl calls openssl with -quiet.

```
/usr/bin/openssl s_client -quiet -verify_quiet -verify_return_error -verify 4
-cert ${SSL_CLIENT_CERT} -key ${SSL_CLIENT_CERT} -servername ${SSL_CLIENT_HOST}
-verify_hostname ${SSL_CLIENT_HOST} -connect ${SSL_CLIENT_HOST}:1453 <
/dev/null ; echo $?
4027DBD1057F0000:error:0A000418:SSL routines:ssl3_read_bytes:tlsv1 alert
unknown ca:ssl/record/rec_layer_s3.c:1605:SSL alert number 48
1
```

now the same without -quiet

```
/usr/bin/openssl s_client -verify_quiet -verify_return_error -verify 4 -cert
${SSL_CLIENT_CERT} -key ${SSL_CLIENT_CERT} -servername ${SSL_CLIENT_HOST}
-verify_hostname ${SSL_CLIENT_HOST} -connect ${SSL_CLIENT_HOST}:1453 <
/dev/null ; echo $?       
verify depth is 4
CONNECTED(00000003)
---
Certificate chain
[snip]
New, TLSv1.3, Cipher is TLS_CHACHA20_POLY1305_SHA256
Server public key is 256 bit
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
Early data was not sent
Verify return code: 0 (ok)
---
DONE
0
```

My guess would be that it might be related to -quiet blocking a potential
password prompt for the private key. but as the key in question is unprotected
it should just work.