Do not depend on deprecated configuration

[Björn Kautler]

The compile configuration as well as the runtime configuration (and testCompile, testRuntime, ...) are deprecated since Gradle 3.4.
Instead to declare dependencies implementation and runtimeOnly (testImplementation, testRuntimeOnly, ...) should be used instead.

You should probably also change this in your own build scripts, but what I mean is that you force your consumers to either use the deprecated configuration or to declare any dependencies twice, in implementation and in server or agent, the first for compiling, the second for packaging.
You use configurations.runtime at https://github.com/rodm/gradle-teamcity-plugin/blob/master/src/main/groovy/com/github/rodm/teamcity/TeamCityServerPlugin.groovy#L85 and https://github.com/rodm/gradle-teamcity-plugin/blob/master/src/main/groovy/com/github/rodm/teamcity/TeamCityAgentPlugin.groovy#L81, but instead you should use configurations.runtimeClasspath which includes runtime (and thus compile), implementation(and thus alsocompile) and runtimeOnly`.

You can see the detailed information at https://docs.gradle.org/current/userguide/java_plugin.html#tab:configurations in the text and the figure.

[Rod MacKenzie]

I've updated the plugin, build scripts, and samples.