Alternative to using default cached features json

[cherylking]

Instead of using a cached default features.json, we could download the maven-metadata.xml and find the latest version available. Then download the features.json for that latest version.

Location of maven-metadata.xml:
https://repo1.maven.org/maven2/io/openliberty/features/features/maven-metadata.xml

Element that contains latest version:

We could use a similar technique to use the latest server schema once the runtime publishes the schema for each openliberty-runtime.