All clusters should default to setting minimum TLS version to TLS 1.2

When a user configures a new cluster the minimum TLS version should be set to TLS 1.2

From looking at https://en.wikipedia.org/wiki/Transport_Layer_Security :

"The PCI Council suggested that organizations migrate from TLS 1.0 to TLS 1.1 or higher before June 30, 2018.[24][25] In October 2018, Apple, Google, Microsoft, and Mozilla jointly announced they would deprecate TLS 1.0 and 1.1 in March 2020.[11]"

Given that an operator can change this we should be "secure by default" and "force" the operator to explicitly open the door for old and deprecated security layers.