Update Gradle wrapper to 9.3

Run the Gradle `wrapper` task twice to update the distribution version & regenerate wrapper to pick up
recent changes per https://docs.gradle.org/current/userguide/gradle_wrapper.html#sec:upgrading_wrapper

    ./gradlew wrapper --gradle-version latest
    ./gradlew wrapper --gradle-version latest

https://docs.gradle.org/9.3.0/release-notes.html

Followup to #658

Signed-off-by: Roger Sheen <roger@infotexture.net>

Author: infotexture

gradle/wrapper/gradle-wrapper.jar

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.3.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME