[ ENH ] Provide authentication failure detail when credentials are provided directly to a Service Class.

[jshcodes]

Describe the issue
Service Class instantiation does not provide an API response, even though a token is generated. On token generation failure, the failure reason is swallowed.

To Reproduce
Create an instance of any Service Class using invalid credentials. You are not provided an immediate response, so any failure reason is hidden. Follow up requests to the API will produce an invalid bearer token error.

Expected behavior
When the token generation fails, provide a place within the class to retrieve the reason.

Environment (please complete the following information):

• OS: All supported
• Python: All supported
• FalconPy: 0.4.0+

Additional context
Discussed in #500

^{Originally posted by morcef January 3, 2022}
Hi,
I am new to this SDK, and I have been starting with using the Detects Service Class (https://falconpy.io/Service-Collections/Detects.html). In the beginning the Detects authenticated() method would return False, and I was having trouble finding the reason.
This seems to be due to the fact that the Service Class will throw away any response that does not have status code 201, and include a token (

falconpy/src/falconpy/_service_class.py

Lines 142 to 156 in 5adb86c

	if _["status_code"] == 201:
	self.token = _["body"]["access_token"]
	self.headers = {"Authorization": f"Bearer {self.token}"}
	# Swap to the correct region if they've provided the incorrect one
	if "X-Cs-Region" not in _["headers"]:
	# GovCloud autodiscovery is not currently supported
	token_region = confirm_base_region(confirmed_base)
	else:
	token_region = _["headers"]["X-Cs-Region"].replace("-", "")
	requested_region = confirm_base_region(confirmed_base)
	if token_region != requested_region:
	self.base_url = confirm_base_url(token_region.upper())
	else:
	self.token = False
	self.headers = {}

).
At this point there was no clear way for me to figure out why this was failing, other than accessing the Detects' auth_object, and executing its token() method a second time to get the actual response. However, my IDE is giving me the following warning when accessing the auth_object: Unresolved attribute reference 'auth_object' for class 'Detects'.