static RequestHeadersBuilder builder(HttpMethod method, String path) {
        requireNonNull(method, "method");
        requireNonNull(path, "path");
        return builder().method(method)
                        .path(path);
    }
Returns a new builder with the specified {@link HttpMethod} and {@code path}.
core/src/main/java/com/linecorp/armeria/common/RequestHeaders.java