Allow suppresing error logs for Core::Remote::Negotiation

[anmarchenko]

What does this PR do?
Adds suppress_logging keyword argument that makes it possible to skip logging error messages for selected error cases.

Usage:

negotiation = Datadog::Core::Remote::Negotiation.new(
  settings, 
  agent_settings, 
  suppress_logging: { no_config_endpoint: true }
)

# no error logged
negotiation.endpoint?("/evp_proxy/v4/") # => false

Motivation:
datadog-ci gem uses Datadog::Core::Remote::Negotiation to check if agent has certain endpoints available(/evp_proxy/v4 and /evp_proxy/v2/) to configure the correct transport for citestcycle events. We do not treat the absence of any of these endpoints as error, just an information for us to choose the correct way to send events.

Currently, this class treats this situation as an error and logs error message thus creating unnecessary noise for the user. This PR aims to fix it by allowing us to skip certain logs.

How to test the change?
Covered by unit tests; default behaviour didn't change.

For Datadog employees:

• If this PR touches code that signs or publishes builds or packages, or handles
  credentials of any kind, I've requested a review from @DataDog/security-design-and-guidance.
• This PR doesn't touch any of that.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.23%. Comparing base (12bfc2f) to head (387bfd2).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3495   +/-   ##
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  Coverage   98.23%   98.23%           
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  Files        1275     1275           
  Lines       75176    75182    +6     
  Branches     3551     3551           
=======================================
+ Hits        73851    73858    +7     
+ Misses       1325     1324    -1     

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