Upgrades gradle to 9.1.0 (#2320)

This supports java 25

Author: spencergibb

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/build.gradle

@@ -25,22 +25,25 @@ ext {
 
 project.version = findProperty('verifierVersion')
 apply plugin: 'groovy'
+apply plugin: 'java'
 apply plugin: "java-gradle-plugin"
 apply from: "$rootDir/gradle/release.gradle"
 //apply plugin: "jacoco"
 
 group = 'org.springframework.cloud'
 
-sourceCompatibility = 17
-targetCompatibility = 17
-
 repositories {
 	mavenLocal()
 	mavenCentral()
 	maven { url "https://repo.spring.io/snapshot" }
 	maven { url "https://repo.spring.io/milestone" }
 }
 
+tasks.withType(JavaCompile).configureEach {
+    sourceCompatibility = JavaVersion.VERSION_17
+    targetCompatibility = JavaVersion.VERSION_17
+}
+
 //Dependencies in all subprojects - https://solidsoft.wordpress.com/2014/11/13/gradle-tricks-display-dependencies-for-all-subprojects-in-multi-project-build/
 task allDeps(type: DependencyReportTask) {}
 task allInsight(type: DependencyInsightReportTask) {}

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.10.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.1.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/src/test/groovy/org/springframework/cloud/contract/verifier/plugin/ContractVerifierTest.groovy

@@ -21,7 +21,7 @@ import org.gradle.api.file.Directory
 import org.gradle.api.internal.project.DefaultProject
 import org.gradle.api.plugins.GroovyPlugin
 import org.gradle.api.plugins.JavaPlugin
-import org.gradle.api.plugins.JavaPluginConvention
+import org.gradle.api.plugins.JavaPluginExtension
 import org.gradle.api.publish.PublicationContainer
 import org.gradle.api.publish.PublishingExtension
 import org.gradle.api.publish.maven.plugins.MavenPublishPlugin
@@ -61,7 +61,7 @@ class ContractVerifierTest {
 		given:
 			ContractVerifierExtension extension = project.extensions.getByType(ContractVerifierExtension)
 			Directory projectDir = project.layout.projectDirectory
-			SourceSet contractTest = project.convention.getPlugin(JavaPluginConvention).getSourceSets().getByName("contractTest")
+			SourceSet contractTest = project.extensions.findByType(JavaPluginExtension).getSourceSets().getByName("contractTest")
 
 		expect:
 			assert contractTest != null
@@ -77,7 +77,7 @@ class ContractVerifierTest {
 			project.plugins.apply(GroovyPlugin)
 			ContractVerifierExtension extension = project.extensions.getByType(ContractVerifierExtension)
 			Directory projectDir = project.layout.projectDirectory
-			SourceSet contractTest = project.convention.getPlugin(JavaPluginConvention).getSourceSets().getByName("contractTest")
+			SourceSet contractTest = project.extensions.getByType(JavaPluginExtension).getSourceSets().getByName("contractTest")
 
 		expect:
 			assert contractTest != null