`newrelic_synthetics_step_monitor` has incorrect documentation

[randompixel]

https://registry.terraform.io/providers/newrelic/newrelic/latest/docs/resources/synthetics_step_monitor

1. As in this screenshot it shows uri as a valid argument.
   
   If you try and use it though you get Error: Unsupported argument

2. The example usage shows a value of enable_screenshot_on_failure_and_script but this is missing from the Argument Reference section.

3. steps > values says "The metadata values related to the step". This isn't very clear what is expected to be input here as neither of the two examples include anything other than NAVIGATE as a type.

[pranav-new-relic]

Thanks for the feedback, @randompixel - we'll take a look at this.