feat(cdc): Add superflag to enable TLS without CA or certs (#7946)

[mangalaman93]

Does the following changes:

• will attempt to connect to Kafka over TLS using the system certs.
• add helper function x.TLSBaseConfig.
• sets the min TLS version to v1.2 along with the minimum cipher suites.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[coveralls]

Coverage: 64.349% (-0.05%) from 64.401% when pulling 4ce799f on aman/tls into 4c1b575 on main.

[all-seeing-code]

@mangalaman93 @Rajakavitha1 when we update main with new flags, I think we should flag it for doc update etc.? What do you think about that? Should we create a new issue/tag someone here/add a label?

[mangalaman93]

we will have to do it for all the changes. We can do it once slash and main are more aligned. We will just go through the list once again I guess.

[matthewmcneely]

@meghalims Kafka CDC (and by extension tls with Kafka) is completely uncovered by tests. Maybe a good task for a junior?