Please enforce a .html extension when saving and offer a default file name, e.g. "audit-log".
To reproduce:
1. Import cert
2. Show Audit Log
3. Save to Disk
4. Open saved file:
```
<html><head>
<title>GnuPG Audit Log Viewer</title>
</head><body>
<div><b>C:/Users/g10/Desktop/certs/testzertifikate_2023/Berta_Boss_0x6D8E6F0D_SECRET.asc (imported with gpg)</b></div><pre>gpg: key 458612006D8E6F0D: public key "Berta Boss <Berta.Boss@demo.gnupg.com>" imported
gpg: key 458612006D8E6F0D: secret key imported
gpg: Total number processed: 1
gpg: imported: 1
gpg: secret keys read: 1
gpg: secret keys imported: 1
</pre><hr><div><b>C:/Users/g10/Desktop/certs/testzertifikate_2023/Berta_Boss_0x6D8E6F0D_SECRET.asc (imported with gpgsm)</b></div><pre>gpgsm: total number processed: 0
gpgsm: error importing certificate: End of file
</pre>
</body></html>
```