feat: rate limit requests for CC

[leogermani]

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Changes proposed in this Pull Request:

Adds a rate limit for Constant Contact request. It should not make more than 4 requests per second.

How to test the changes in this Pull Request:

1.Smoke test a Constant Contact connection

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully ran tests with your changes locally?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 23.07%. Comparing base (5ec8c54) to head (9692d02).
Report is 5 commits behind head on trunk.

Additional details and impacted files

@@             Coverage Diff              @@
##              trunk    #1714      +/-   ##
============================================
+ Coverage     23.00%   23.07%   +0.07%     
- Complexity     2710     2713       +3     
============================================
  Files            49       49              
  Lines         10751    10761      +10     
============================================
+ Hits           2473     2483      +10     
  Misses         8278     8278              

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[github-actions]

Hey @leogermani, good job getting this PR merged! 🎉

Now, the needs-changelog label has been added to it.

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[matticbot]

🎉 This PR is included in version 3.6.0-alpha.1 🎉

The release is available on GitHub release

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