Update gradlew wrapper to 4.10.3

Motivation:
The existing gradlew wrapper version doesn't support JDK11.

Modifications:
- Update to 4.10.3 which does support JDK11.

Result:
JDK11 support.

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
-distributionUrl=http\://services.gradle.org/distributions/gradle-4.3-bin.zip
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-zipStorePath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.3-bin.zip