Remove the need for the uber jar

[fab-10]

At the moment this plugin is release as a single uber jar, that packs all the dependencies inside, including most of the Besu's dependencies, this create friction and is error prone since it is easy to have different versions of the same class that results in errors at runtime.
For this we want to remove the uber jar, and just create a standard library jar that only contains the classes of the plugin.
Note that the final distribution of the plugin, could also contain additional dependencies that are not already provided by Besu, for example at the moment jackson-dataformat-yaml jar needs to be installed along with the plugin jar in the Besu plugins dir to work.