Publish otel.spotless-conventions?

[trask]

Pros:

This would enable us to use it across all 4 java repos (core, instrumentation, contrib, docs).

In particular, instrumentation repo has many standalone gradle modules, which currently requires copying spotless configuration across each one (https://github.com/open-telemetry/opentelemetry-java-instrumentation/pull/5058).

Cons:

It's really just for use on OpenTelemetry projects, given that it adds our license header, as opposed to something public for others to use:

/*
 * Copyright The OpenTelemetry Authors
 * SPDX-License-Identifier: Apache-2.0
 */

[jkwatson]

How/where would we do this, do you think?

[anuraaga]

It's always been a goal to publish all the conventions to use among our three repos to reduce code duplication. But keeping the code in sync hasn't been quite annoying enough to prioritize that yet, maybe it's important now though.