Drop unwanted + unused brp-* scripts
    
    If java people say brp-java-repack-jars is not needed then it
    probably isn't (#1235770). brp-implant-ident-static hasn't been enabled
    in 13+ years, I THINK it's safe to say its not critically needed.
    
    Leaving the actual scripts in the repo for now (amusement for
    archeologists of future generations, eh?)