Exclude fields from query params if the fields are already configured for path params or body. #1041

// ## Rules for HTTP mapping
//
// 1. Leaf request fields (recursive expansion nested messages in the request
//    message) are classified into three categories:
//    - Fields referred by the path template. They are passed via the URL path.
//    - Fields referred by the [HttpRule.body][google.api.HttpRule.body]. They are passed via the HTTP
//      request body.
//    - All other fields are passed via the URL query parameters, and the
//      parameter name is the field path in the request message. A repeated
//      field can be represented as multiple query parameters under the same
//      name.
//  2. If [HttpRule.body][google.api.HttpRule.body] is "*", there is no URL query parameter, all fields
//     are passed via URL path and HTTP request body.
//  3. If [HttpRule.body][google.api.HttpRule.body] is omitted, there is no HTTP request body, all
//     fields are passed via URL path and URL query parameters.