Regular feature names are extracted together with historical features during feature metadata extraction.
Based on this, feature checks in tests are validated to use only known features to prevent tests from
being silently disabled due to a invalid or misspelled feature name.
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Co-authored-by: Lorenzo Dematte <lorenzo.dematte@elastic.co>
This introduces a new getHistoricalFeatures() method on ESRestTestCase
which returns a map of historical feature version mappings loaded from
FeatureSpecification implementations from any plugins/modules in use
by the current test suite. The mappings are generated by a new Gradle
task at build time, and then injected into the test runtime as a
System property.
