Add steps to playbook on how to clear robots.txt cahce

[sean1588]

Add steps to playbook on how to clear the cache on Google’s end. If this is not something that can be done by “anyone”, add a note to contact someone on the docs team who can.

see: https://developers.google.com/search/docs/crawling-indexing/robots/submit-updated-robots-txt#refresh-googles-robots.txt-cache

related to: https://github.com/pulumi/docs/issues/8742

[sean1588]

this is related to the overall create playbook issue here: https://github.com/pulumi/docs/issues/8742