Refactor and define Gradle snapshot, milestone and release builds in terms of the Spring Build Conventions Gradle Plugins, io.spring.gradle.convention.Utils class.

build.gradle

@@ -1,8 +1,10 @@
+import io.spring.gradle.convention.Utils
+
 buildscript {
   ext {
-    snapshotBuild = version.endsWith('SNAPSHOT')
-    releaseBuild = version.endsWith('RELEASE')
-    milestoneBuild = !(releaseBuild || snapshotBuild)
+    snapshotBuild = Utils.isSnapshot(project)
+    milestoneBuild = Utils.isMilestone(project)
+    releaseBuild = Utils.isRelease(project)
   }
   repositories {
     mavenCentral()
@@ -54,6 +56,7 @@ subprojects {
 
 description = 'Spring Test Framework for Apache Geode'
 
+// Define dependency version overrides.
 //ext['spring.version'] = "$springVersion"
 ext['spring-framework.version'] = "$springVersion"
 ext['spring-data-bom.version'] = "$springDataBomVersion"