public AbstractRequestContextBuilder eventLoop(EventLoop eventLoop) {
        this.eventLoop = requireNonNull(eventLoop, "eventLoop");
        return this;
    }
Sets the {@link EventLoop} that handles the request.
If not set, one of the {@link CommonPools#workerGroup()} is used.
core/src/main/java/com/linecorp/armeria/common/AbstractRequestContextBuilder.java