updated gradlew to current version

Signed-off-by: Konstantin Läufer <laufer@cs.luc.edu>

Author: klaeufer

gradle.properties

@@ -2,6 +2,3 @@
 org.gradle.jvmargs=-Xmx2048m
 org.gradle.parallel=true
 org.gradle.caching=true
-
-# Use Java 21 for Gradle daemon (fixes compatibility with Kotlin compiler and Java 25)
-org.gradle.java.home=/Users/laufer/.sdkman/candidates/java/21.0.8-tem

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.11.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.1.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME