[improve][meta] Upgrade Oxia client to 0.8.0 - #25962

Motivation

• Upgrade the Oxia Java client used by Pulsar metadata store to the latest 0.8.0 release.
• Keep the Oxia testcontainers artifact on 0.7.4 because 0.8.0 is not published for that module on Maven Central.

Modifications

• Bumped io.github.oxia-db:oxia-client to 0.8.0 in the Gradle version catalog.
• Split the Oxia testcontainers version so tests continue to resolve the currently published 0.7.4 artifact.
• Updated the binary LICENSE jar entries for the Oxia client artifacts and the new Failsafe runtime dependency.
• Adjusted the Oxia config-loading test to reflect the 0.8.0 client internals after SessionFactory was removed.
• Adapted the Oxia range-scan consumer to the 0.8.0 API where onNext returns whether scanning should continue.

Testing

• ./gradlew :pulsar-metadata:compileJava --rerun-tasks
• ./gradlew :pulsar-metadata:compileTestJava
• ./gradlew :pulsar-metadata:test --tests org.apache.pulsar.metadata.MetadataStoreTest.testOxiaLoadConfigFromFile
• ./gradlew :distribution:pulsar-server-distribution:checkBinaryLicense