chore: promote aepfli to java maintainer

[toddbaert]

@aepfli has made significant contributions to the OpenFeature Java ecosystem. They have:

• conceived and built our Junit testing extension, allowing simple and consistent testing via annotations: https://github.com/open-feature/java-sdk-contrib/tree/main/tools/junit-openfeature
• have made numerous contributions to the SDK and flagd provider
• they've been active contributors to the community, representing OpenFeature at conferences and in fact building our community management automation in use in this PR

Full disclosure, @aepfli is a member of my organization (Dynatrace) so I will be nominating them but seeking approval from at least 2 non-Dynatrace maintainers or TC/GC members.

@aepfli please :+1: or approve this yourself as well!