chore: pin mparticle dependency to [5.0,6.0) range

Replace open-ended `+` resolution in the standalone build with a bounded
range so the kit doesn't pick up `com.mparticle:android-kit-plugin:6.0.0-rc.1`
(published to Maven Central on 2026-05-22) when built outside the
mparticle-android-sdk monorepo.

The mparticle-android-sdk CI now passes `-Pversion=<sdk-version>`
explicitly, so this range only kicks in for ad-hoc/external standalone
builds.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: jamesnrokt

build.gradle

@@ -1,7 +1,9 @@
 buildscript {
     ext.kotlin_version = '2.0.20'
     if (!project.hasProperty('version') || project.version.equals('unspecified')) {
-        project.version = '+'
+        // Bounded range avoids resolving to 6.0.0-rc.1+ on Maven Central when
+        // built standalone. The mparticle-android-sdk CI passes -Pversion explicitly.
+        project.version = '[5.0,6.0)'
     }
 
     repositories {