Specify example dependencies versions for generated client

The generated client is built to work with specific version. It is fine to keep it open which versions are used in the end. But it would be much more useful to specify some versions at least as an example in the documentation here: https://guardrail.dev/scala/dropwizard/

Otherwise you leave it as an open quest for each and every developer trying to integrate it, and go through the hassle of figuring out compatible versions on his own. Specifying at least some compatible versions as an example would be already of a use.

Example (in my case for JavaClient):
```sbt
libraryDependencies ++= Seq(
"org.asynchttpclient" % "async-http-client" % "2.12.1",
"com.fasterxml.jackson.core" % "jackson-core" % "2.12.0",
"com.fasterxml.jackson.core" % "jackson-databind" % "2.12.0",
"com.fasterxml.jackson.core" % "jackson-annotations" % "2.12.0",
"com.fasterxml.jackson.datatype" % "jackson-datatype-jdk8" % "2.12.0",
"com.fasterxml.jackson.datatype" % "jackson-datatype-jsr310" % "2.12.0",
),
```

Open the Scala Dropwizard documentation at https://guardrail.dev/scala/dropwizard/ and find the generated-client dependency example. Add representative compatible dependency versions, using the JavaClient list in the issue as a starting reference; done when readers have a copyable versioned example instead of needing to determine every version themselves.

Written by the indexing model from the issue text.