Minor improvement in gradle helidon quickstart

[mavek87]

Hi I suggest a minor improvement in the gradle helidon quickstart (https://github.com/helidon-io/helidon-examples/blob/4.2.1/examples/quickstarts/helidon-quickstart-se/build.gradle)

In the build.gradle file I suggest to change the custom task into this:

tasks.register("copyLibs", Copy) {
    from configurations.runtimeClasspath
    into 'build/libs/libs'
}

This is a more modern way to define a custom gradle task which is lazy instead of the eager task currently used.