feat: widen urbanairship-core dependency to any 20.x

[jamesnrokt]

Summary

• Replace the pinned api 'com.urbanairship.android:urbanairship-core:20.3.0' with the bounded range [20.3.0,21.0.0).
• Lets partners adopt any 20.x release (currently 20.4.0–20.7.2 are published) without waiting for a new kit release.
• Floor stays at 20.3.0 — the previously tested baseline; we don't claim support for 20.0–20.2.
• Closed upper bound at 21.0.0 keeps a future Airship 21.x out of the resolved set; bumping to 21.x will be an explicit kit-release decision.

Motivation

A partner using this kit wants to upgrade their Airship integration to 20.6.0. Today the hard pin at 20.3.0 forces them to either downgrade the rest of their app or wait for a kit release.

How partners get a specific 20.x

After this lands, consumers have two options:

1. Do nothing — Gradle resolves the range to the highest compatible 20.x.
2. Pin in their app — implementation 'com.urbanairship.android:urbanairship-core:20.6.0'. Gradle's conflict resolution picks the explicit pin.

Test plan

• ./gradlew lint testRelease publishReleaseLocal succeeds standalone against the top of the range (20.7.2).
• ./gradlew lint testRelease publishReleaseLocal succeeds against the floor (20.3.0) — -Pversion=... plus a forced urbanairship-core:20.3.0 in a scratch consumer.
• Smoke-test a sample app pinning 20.6.0 to confirm the kit + Airship 20.6.0 coexist.

Release note

The kit's next release should be a minor bump (e.g., 5.x.0 → 5.(x+1).0) since it changes the public dependency contract. Consumers already on a previous kit version are unaffected until they upgrade the kit.

🤖 Generated with Claude Code

[samdozor]

The issue with this is that it will cause non-repeatable builds for all clients - unless they specifically put the airship version in their own build gradle. So we need to tell all clients to do that. The client asking for this will need to specifically put airship in their gradle to ensure a repeatable build - so why not have that client do something like this, rather than asking all clients to change?

dependencies {
    implementation('com.mparticle:android-urbanairship-kit:5+') {
        exclude group: 'com.urbanairship.android', module: 'urbanairship-core'
    }
    implementation 'com.urbanairship.android:urbanairship-core:21.0.0
}