security/easy-rsa: update to 3.0.8

• Provide --version option (#372)
• Version information now within generated certificates like on *nix
• Fixed issue where gen-dh overwrote existing files without warning (#373)
• Fixed issue with ED/EC certificates were still signed by RSA (#374)
• Added support for export-p8 (#339)
• Clarified error message (#384)
• 2->3 upgrade now errors and prints message when vars isn't found (#377)