catchpoints: log ledger download failures

[cce]

Summary

I noticed we have logging around catchpoint ledger file download success, and catchpoint block download errors, but no logging for catchpoint ledger file download failures. This provides more logging about failures related to ledger file timeout & retry issues like those seen with #5503.

Test Plan

Logging only changes, existing tests should pass.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Project coverage is 51.83%. Comparing base (c60db8d) to head (b7aeb40).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
catchup/catchpointService.go	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6227      +/-   ##
==========================================
- Coverage   51.86%   51.83%   -0.04%     
==========================================
  Files         643      643              
  Lines       86382    86384       +2     
==========================================
- Hits        44804    44774      -30     
- Misses      38716    38740      +24     
- Partials     2862     2870       +8     

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