feat: add override method for optional params in java client

[millotp]

🧭 What and Why

Optional parameters are required in java, unless you provide a different method definition that overrides and call the first method.

This PR adds a method only for required parameters, and provide the default or null value for the optional parameters.
The ideal way to do this would be to have a different method for each set of parameters, like:

GetLogsResponse getLogs() { 
  return getLogs(0, 10, null, "all");
}
GetLogsResponse getLogs(int offset) { 
  return getLogs(offset, 10, null, "all"); 
}
GetLogsResponse getLogs(int offset, int length) { 
  return getLogs(offset, length, null, "all"); 
}
GetLogsResponse getLogs(int offset, int length, String indexName) { 
  return getLogs(offset, length, indexName, "all"); 
}

But I have no idea how to do it in mustache

🧪 Test

Tests are coming soon with the CTS.

[damcou]

Weird but ok :p