[SPARK-45541][CORE] Add SSLFactory

[hasnain-db]

What changes were proposed in this pull request?

As titled - add a factory which supports creating SSL engines, and a corresponding builder for it. This will be used in a follow up PR by the TransportContext and related files to add SSL support.

Why are the changes needed?

We need a mechanism to initialize the appropriate SSL implementation with the configured settings (such as protocol, ciphers, etc) for RPC SSL support.

Does this PR introduce any user-facing change?

No

How was this patch tested?

existing tests. This will be more thoroughly tested in a follow up PR which adds callsites to it. It has been integration tested as part of #42685

Was this patch authored or co-authored using generative AI tooling?

No

[hasnain-db]

test failures looked unrelated, retrying now though.

[hasnain-db]

cc @mridulm@JoshRosen now that tests are green

[mridulm]

Took a quick pass through the change, will go over the PR again in more detail later this week.

[mridulm]

Just a couple of nits.
Can you update to master and retrigger the tests please ? Let us see if we can get a clean build (though the failures are not related)

[hasnain-db]

will re-request review once CI comes back

[mridulm]

Looks good to me, will wait for CI to succeed.

[hasnain-db]

thanks! some jobs failed, rerunning them so hopefully there is a green CI in the morning

[mridulm]

The test failure is unrelated to this PR.
Merging to master.

Thanks for fixing this @hasnain-db !