Remove second cache in bitcoin tests

[wileyj]

Removes the duplicate cache step in bitcoin-tests that reproduces the already existing test_archive.tar.zst, built only with stacks-node as opposed to the existing (and downloaded) cache built with all binaries.

comparing develop to the branch being PR'ed here (which is develop with the cache step removed) i see both ci runs of bitcoin-tests result in 266 tests to be run.

This branch simply uses the already existing nextest cache that is built for all CI runs in the Create Test Cache job (and is subsequently used for all test runs vs rebuilding).

develop: https://github.com/wileyj/stacks-core/actions/runs/21649775746/job/62412455861#step:7:35
chore/dedupe_bitcoin_test_cache: https://github.com/wileyj/stacks-core/actions/runs/21650652585/job/62415354269#step:6:35

because there are so many tests being run though, both actions will take quite a bit of time to run completely - but it does result in a few minutes saved before the tests start (00:09:45 vs 00:02:07 - 7 minutes and 38 seconds faster).

small improvement, but worth doing.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.39%. Comparing base (1c5bc67) to head (686ae77).
⚠️ Report is 16 commits behind head on develop.

❌ Your project status has failed because the head coverage (73.39%) is below the target coverage (80.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #6852      +/-   ##
===========================================
+ Coverage    68.54%   73.39%   +4.85%     
===========================================
  Files          593      593              
  Lines       358682   358727      +45     
===========================================
+ Hits        245850   263285   +17435     
+ Misses      112832    95442   -17390     

see 386 files with indirect coverage changes

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[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.