Upgrade to Gradle 9.2

This commit upgrades the build to use Gradle 9.2 and reinstates the use
of the Groovy safe-navigation operator (?.) in framework-api.gradle.

See gradle/gradle#35049
See d038269
Closes spring-projectsgh-35713

Author: sbrannen

framework-api/framework-api.gradle

@@ -98,12 +98,9 @@ tasks.register('schemaZip', Zip) {
 	moduleProjects.each { module ->
 		def Properties schemas = new Properties();
 
-		def schemaFile = module.sourceSets.main.resources.find {
+		module.sourceSets.main.resources.find {
 			(it.path.endsWith("META-INF/spring.schemas") || it.path.endsWith("META-INF\\spring.schemas"))
-		}
-		if (schemaFile != null) {
-			schemaFile.withInputStream { schemas.load(it) }
-		}
+		}?.withInputStream { schemas.load(it) }
 
 		for (def key : schemas.keySet()) {
 			def shortName = key.replaceAll(/http.*schema.(.*).spring-.*/, '$1')

gradle/wrapper/gradle-wrapper.jar

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.1.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME