chore: update fillform example to use async check

[VikaCep]

The browser squad now recommends using the async check polyfill in all code examples and has updated the fillform example in https://github.com/grafana/xk6-browser/tree/main/examples

In order to be consistent, the fillform example for synthetics browser checks has been updated as well.

[w1kman]

I don't think lo is a suitable variable name in the context of being an example.

[w1kman]

I would skip abbreviations in example code (with some exceptions).
I assume lo is an abbreviation for "locator" (which resolves into an element-ish).
I suggest that we change lo into element.

[VikaCep]

Good catch! changed it 👍

[ckbedwell]

Do we know if the polyfill check registers for our assertions table in the dashboard correctly? I copied this new example and have had it running for an hour.

[VikaCep]

Do we know if the polyfill check registers for our assertions table in the dashboard correctly? I copied this new example and have had it running for an hour.

This is odd, I'm seeing the assertions correctly for this script

Are they still not showing up?

[w1kman]

LGTM 🥇