Reduce the matrix fanout of interop runner

Reduce the matrix fanout of interop runner

Recent test additions have increased the number of jobs spawned by the
interop runner test which exceeds the maximum allowed.

This occurs because the matrix expands to:
7 server elements
6 client elements
7 tests
2 test steps (client interop and server interop

Because of how github ci does matrix expansion, this results in
2 * 7 * 7 * 6 = 588

But most of those are invalid because each of the 2 steps only considers
either the client or server elements, and so get rerun multiple times

Alter the steps to be individual jobs, each with their own reduced
matrix to only run each relevant test once, limiting our job count to
at most 49 jobs.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Saša Nedvědický <sashan@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/26275)