chore(deps): update dependency gradle to v9 (#757)

* chore(deps): update dependency gradle to v9

* fix war test app file resolution

---------

Co-authored-by: elastic-renovate-prod[bot] <174716857+elastic-renovate-prod[bot]@users.noreply.github.com>
Co-authored-by: Sylvain Juge <763082+SylvainJuge@users.noreply.github.com>

Author: elastic-renovate-prod[bot]

gradle/wrapper/gradle-wrapper.jar

@@ -1,7 +1,7 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionSha256Sum=bd71102213493060956ec229d946beee57158dbd89d0e62b91bca0fa2c5f3531
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.14.3-bin.zip
+distributionSha256Sum=8fad3d78296ca518113f3d29016617c7f9367dc005f932bd9d93bf45ba46072b
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.0.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

gradle/wrapper/gradle-wrapper.properties

@@ -56,7 +56,7 @@ tasks.test {
 
   // depends on the packaged test app war file
   dependsOn(":smoke-tests:test-app-war:assemble")
-  def warFile = project.configurations.warOnly.files.stream().findFirst().get()
+  def warFile = project.configurations.warOnly.files.stream().filter { it.name.endsWith(".war")}.findFirst().get()
   inputs.files(layout.files(warFile))
 
   doFirst {