feat: set a User Agent here

[sabotagebeats]

Overview

Provide a simple overview of what you wish to see added. Please include:

• What you are trying to do requests should have user agent
• Why Ape's current functionality is inadequate to address your goal doesn't have user agent

Specification

Something like: f"ape-etherscan {vers} python {py_vers}"

from ape import config

requests.get(..., headers=config.REQUST_HEADER, ...)

Describe the syntax and semantics of how you would like to see this feature implemented. The more detailed the better!

Remember, your feature is much more likely to be included if it does not involve any breaking changes.

Dependencies

none