Optimize RcsCcsCommonYamlTestSuiteIT and unmute tests

[drempapis]

The RcsCcsCommonYamlTestSuiteIT suite is failing multiple tests with the following error:

java.lang.Exception: Test abandoned because suite timeout was reached.

A global suite timeout is currently set to 20 minutes:

@TimeoutSuite(millis = 20 * TimeUnits.MINUTE)

While increasing the timeout is a valid short-term workaround, it only defers the issue. As the test set grows or individual tests become more complex, the suite may eventually could exceed the new limit as well.

This PR focuses on optimizing the code executed before each test. Specifically:

• Initializes and verifies CCS only once

• Caches the combined features / versions / OS, instead of recomputing per test.

I executed the test

./gradlew ":qa:ccs-common-rest:yamlRestTest" --tests "org.elasticsearch.test.rest.yaml.RcsCcsCommonYamlTestSuiteIT" -Dtests.method="test {p0=search.vectors/*}" -Dtests.seed=B06EC72911CB2

Getting the execution times 4m 34s vs 2m 40s, comparing the main vs the optimized code.

Closes: #131225, #131348, #131484, #131598, #131565, #131967

[elasticsearchmachine]

Pinging @elastic/es-search-foundations (Team:Search Foundations)

[benchaplin]

Thanks @drempapis - let's see if your other changes still buy us those speedups. If not I'm happy to think through the 1 vs. 2 node issue more carefully.