Update supported SSLyze version to v0.12

[mathias-nyman]

Required adaptation for the following changes:

• printout for --version is now just the number
• publicKeySize is now a number
• hsts can be found with unique tag httpStrictTransportSecurity
• heartbleed can be found with unique tag openSslHeartbleed

[mathias-nyman]

Fixes issue https://github.com/F-Secure/mittn/issues/26.

[mathias-nyman]

Addressed TanyaGaleyev's comments.