Replace blutgang with spamoor replicas

[fridrik01]

This PR replaces the use of a load balancer (blutgang by default but ngingx also suppported) when running a single instance of spamoor with a running multiple replicas of spamoor where each target a single execution client.

This replicates how we conduct testing in our staging env we have had issues with blutgang where it was running unstably and restarting frequently. Also when scanning the blutgang logs it frequently removes nodes from the active set due to them falling behind (and then later adding them back) resulting in spamoor frequently hitting the same rpc node.

NOTE: The e2e CI test is failing, this is fixed in followup PR where we remove blutgang/nginx altogether from all integration tests

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 31.15%. Comparing base (39c4ebe) to head (a6c6111).

Additional details and impacted files

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##             main    #2370   +/-   ##
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  Coverage   31.15%   31.15%           
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  Files         346      346           
  Lines       15438    15438           
  Branches       20       20           
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  Hits         4810     4810           
  Misses      10289    10289           
  Partials      339      339