Speed up integration tests

[obycode]

Description

This is a quick attempt to address #6495 by reducing the pox cycle length (20+5 --> 10+3) and compressing the epoch heights.

Applicable issues

• fixes Reduce time spent reaching latest epoch in integration tests #6495

Additional info (benefits, drawbacks, caveats)

Checklist

• Test coverage for new or modified code paths
• Changelog is updated
• Required documentation changes (e.g., docs/rpc/openapi.yaml and rpc-endpoints.md for v2 endpoints, event-dispatcher.md for new events)
• New clarity functions have corresponding PR in clarity-benchmarking repo
• New integration test(s) added to bitcoin-tests.yml

[codecov]

Codecov Report

❌ Patch coverage is 0% with 339 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.51%. Comparing base (87c4373) to head (0965db7).
⚠️ Report is 43 commits behind head on develop.

Files with missing lines	Patch %	Lines
stacks-node/src/tests/nakamoto_integrations.rs	0.00%	339 Missing ⚠️

❌ Your project check has failed because the head coverage (71.51%) is below the target coverage (80.00%). You can increase the head coverage or adjust the target coverage.

❗ There is a different number of reports uploaded between BASE (87c4373) and HEAD (0965db7). Click for more details.

HEAD has 98 uploads less than BASE

Flag	BASE (87c4373)	HEAD (0965db7)
	136	38

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #6517      +/-   ##
===========================================
- Coverage    78.84%   71.51%   -7.33%     
===========================================
  Files          563      565       +2     
  Lines       345414   346732    +1318     
===========================================
- Hits        272350   247981   -24369     
- Misses       73064    98751   +25687     

Files with missing lines	Coverage Δ
stacks-node/src/tests/nakamoto_integrations.rs	0.00% <0.00%> (-78.13%)	⬇️

... and 209 files with indirect coverage changes

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