feat: remove holesky support

[khalifaa55]

Changes:

• Remove Holesky from Sedge supported networks
• Support distributed validator on Sepolia instead of Holesky
• Remove Holesky from Lido CSM supported networks
• Update tests

Types of changes

What types of changes does your code introduce?
Put an x in the boxes that apply

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Other (please describe):

Testing

Requires testing

• Yes
• No

In case you checked yes, did you write tests?

• Yes
• No

[codecov-commenter]

Codecov Report

❌ Patch coverage is 85.71429% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 24.11%. Comparing base (0ae4840) to head (631ba31).
⚠️ Report is 1 commits behind head on develop.

Files with missing lines	Patch %	Lines
cmd/lido-exporter/cli/lido_exporter.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #529      +/-   ##
===========================================
- Coverage    24.13%   24.11%   -0.03%     
===========================================
  Files          121      121              
  Lines        19672    19671       -1     
===========================================
- Hits          4748     4743       -5     
- Misses       14380    14382       +2     
- Partials       544      546       +2     

Flag	Coverage Δ
unittests	24.11% <85.71%> (-0.03%)	⬇️

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