fix tls-grab option with ztls mode

[RamanaReddy0M]

#1142 -tls-grab option doesn't work with -ztls mode

[RamanaReddy0M]

✗ ./httpx -u google.com -ztls -tls-grab -json -silent | jq .tls
{
  "host": "google.com",
  "port": "443",
  "probe_status": true,
  "tls_version": "tls12",
  "cipher": "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
  "not_before": "2023-05-29T08:16:17Z",
  "not_after": "2023-08-21T08:16:16Z",
  "subject_dn": "CN=*.google.com",
  "subject_cn": "*.google.com",
  "subject_an": [
    "*.google.com",
    "*.appengine.google.com",
    "*.bdn.dev",
    "*.origin-test.bdn.dev",
    "*.cloud.google.com",
    "*.crowdsource.google.com",
    "*.datacompute.google.com",
    "*.google.ca",
      ...
  ],
  "serial": "DB:68:49:6B:4E:17:50:F5:12:99:FA:7B:ED:B1:22:B8",
  "issuer_dn": "CN=GTS CA 1C3, O=Google Trust Services LLC, C=US",
  "issuer_cn": "GTS CA 1C3",
  "issuer_org": [
    "Google Trust Services LLC"
  ],
  "fingerprint_hash": {
    "md5": "5c86a077182cd855f21b8d80b363100f",
    "sha1": "a8b52bde3bdbfbab1b787ae68fde23236cab863b",
    "sha256": "2aa97ca45c98e14d3cd12af65b396f1a51731b94ec4b5f705a8920116775adc2"
  },
  "wildcard_certificate": true,
  "tls_connection": "ztls"
}

[Mzack9999]

lgtm!

$ go run . -u scanme.sh -ztls -tls-grab -json -silent | jq .tls
{
  "host": "scanme.sh",
  "port": "443",
  "probe_status": true,
  "tls_version": "tls12",
  "cipher": "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
  "self_signed": true,
  "mismatched": true,
  "not_before": "2022-06-07T15:18:51Z",
  "not_after": "2032-06-04T15:18:51Z",
  "subject_dn": "CN=scanme, O=pd",
  "subject_cn": "scanme",
  "subject_org": [
    "pd"
  ],
  "serial": "EF:00:99:77:D2:1E:A4:3F",
  "issuer_dn": "CN=scanme, O=pd",
  "issuer_cn": "scanme",
  "issuer_org": [
    "pd"
  ],
  "fingerprint_hash": {
    "md5": "eacf1e9b4acca9168b43f84a9bfaa7c5",
    "sha1": "550837ef878d58c92820e9498e3807c6bd7184ec",
    "sha256": "ebbf69a9e7ba65b51fa12cd44105055c2c2c250706e9795fab219d3d5dff5fac"
  },
  "tls_connection": "ztls"
}