build: add cargo-binstall metadata

[sylvestre]

Point cargo-binstall at the cargo-dist release artifacts (findutils-{target}.tar.xz, zip on Windows) so 'cargo binstall findutils' installs prebuilt binaries instead of building from source.

[codspeed-hq]

Merging this PR will not alter performance

✅ 20 untouched benchmarks

---

_{Comparing sylvestre:binstall (0269da2) with main (58c3af0)}

[github-actions]

Commit 0269da2 has test result changes:

bfs testsuite:

Test results comparison:
  Current:   TOTAL: 314 / PASSED: 267 / FAILED: 41 / SKIPPED: 6
  Reference: TOTAL: 313 / PASSED: 267 / FAILED: 40 / SKIPPED: 6

Changes from main branch:
  TOTAL: +1
  PASSED: +0
  FAILED: +1

New test failures (1):
  - gnu/files0_from_ok

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.93%. Comparing base (58c3af0) to head (0269da2).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #814   +/-   ##
=======================================
  Coverage   91.93%   91.93%           
=======================================
  Files          35       35           
  Lines        7253     7253           
  Branches      378      378           
=======================================
  Hits         6668     6668           
  Misses        443      443           
  Partials      142      142           

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