Ref #612: Use detachedConfiguration() to cleanly resolve old API artifact with Gradle 8.2+

[jbonofre]

Before this PR

With Gradle 8.2+, revapi plugin doesn't detect any ABI/API breaks.
The reason is because it doesn't resolve the right artifacts for the old API: it always compares new API with new API.
The old API artifact is actually resolved using the project version (so the SNAPSHOT version) instead of the old version defined.

After this PR

Using detachedConfiguration() in the OldApiConfigurations allow to not get the project default artifact but actually the old API one (correct).

Possible downsides?

This change works with any Gradle version. The only downside with detachedConfiguration() is when using --configuration-cache as detached configurations can't be cached.

This closes #612

[palantirtech]

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[changelog-app]

Generate changelog in changelog/@unreleased

What do the change types mean?

• feature: A new feature of the service.
• improvement: An incremental improvement in the functionality or operation of the service.
• fix: Remedies the incorrect behaviour of a component of the service in a backwards-compatible way.
• break: Has the potential to break consumers of this service's API, inclusive of both Palantir services
  and external consumers of the service's API (e.g. customer-written software or integrations).
• deprecation: Advertises the intention to remove service functionality without any change to the
  operation of the service itself.
• manualTask: Requires the possibility of manual intervention (running a script, eyeballing configuration,
  performing database surgery, ...) at the time of upgrade for it to succeed.
• migration: A fully automatic upgrade migration task with no engineer input required.

Note: only one type should be chosen.

How are new versions calculated?

• ❗The break and manual task changelog types will result in a major release!
• 🐛 The fix changelog type will result in a minor release in most cases, and a patch release version for patch branches. This behaviour is configurable in autorelease.
• ✨ All others will result in a minor version release.

Type

• Feature
• Improvement
• Fix
• Break
• Deprecation
• Manual task
• Migration

Description

Ref #612: Use detachedConfiguration() to cleanly resolve old API artifact with Gradle 8.2+

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