@Override
    public DefaultServiceConfigSetters setHeader(CharSequence name, Object value) {
        requireNonNull(name, "name");
        requireNonNull(value, "value");
        ensureNoPseudoHeader(name);
        defaultHeaders.setObject(name, value);
        return this;
    }
A default implementation of {@link ServiceConfigSetters} that stores service related settings
and provides a method {@link DefaultServiceConfigSetters#toServiceConfigBuilder(Route, String, HttpService)}
to build {@link ServiceConfigBuilder}.
core/src/main/java/com/linecorp/armeria/server/DefaultServiceConfigSetters.java