[bug#46049] [PATCH] services: nginx: Add ssl-protocols option.

[mirai]

How about leaving it empty by default and writing the directive to file only if 
a value is present?
This way the defaults are automatically chosen by nginx. (as they can drift due 
to automatic protocol
support detection or as newer protocols roll out)

About making recommendations in the docs, I'd suggest linking it directly to 
Mozilla's website
rather than duplicating it and risk ending up with outdated advice.