For example:

    ssl_min_protocol_version = 'TLSv1.1'
    ssl_max_protocol_version = 'TLSv1.2'
Reviewed-by: Steve Singer <steve@ssinger.info>
Discussion: https://www.postgresql.org/message-id/flat/1822da87-b862-041a-9fc2-d0310c3da173@2ndquadrant.com