opentelemetry-js: AWS lambda - process is killed before the span is being exported

This is a simple scenario of lambda function

exports.handler = ( async ( event, ctx ) => {
    const span = tracer.startSpan('test');
    span.end();
    return 'done';
} );

The span is not exported correctly as lambda seems to kill the process before it gets exported When adding some timeout before the process get killed the span iss exported

exports.handler = ( async ( event, ctx ) => {
    const span = tracer.startSpan('test');
    span.end();
    await new Promise((resolve)=> {
        setTimeout(()=> {
            resolve();
        }, 500);
    })
    
    return 'done';
} );

So the idea is to implement some async method either on tracer or exporter or change the exporter method shutdown to be a promise and to be resolved when the last exports is sent successfully

WDYT ?