Replace explicit directions for missing key to be service-agnostic

[SavagePencil]

An enterprise customer was confused when they were directed to Griptape Cloud to generate keys.

In

griptape/griptape/drivers/event_listener/griptape_cloud_event_listener_driver.py

Line 52 in caca04c

"You can generate a Griptape Cloud API Key by visiting https://cloud.griptape.ai/keys . "

we specifically direct customers to https://cloud.griptape.ai/keys, but this may not be true for enterprise customers. Update the error message to be service- and URL- agnostic. Confirm there are no other instances throughout the codebase.

[a-b-h-a-y-s-h-i-n-d-e]

Hey @SavagePencil I would like to contribute to this issue,

Proposed change

"Please obtain a Griptape Cloud API Key from your organization's Griptape Cloud service or contact your administrator. "

The link https://cloud.griptape.ai/keys is currently invalid but, but since we are updating the message to be both service and URL agnostic, the link will no longer be a problem.

I also searched through the codebase ( using grep for API-related strings ) and can confirm there are no instances that need to be updated.

Also, if this phrasing doesn't fit well, please feel free to suggest a better wording.