chore(deps): update rand crate to v0.8.6

[xtqqczze]

No description provided.

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/cp/sparse-to-pipe. tests/cp/sparse-to-pipe is passing on 'main'. Maybe you have to rebase?
GNU test failed: tests/uniq/uniq-perf. tests/uniq/uniq-perf is passing on 'main'. Maybe you have to rebase?
Skip an intermittent issue tests/date/date-locale-hour (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/rm/isatty (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/tail/tail-n0f (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/tail/symlink (passes in this run but fails in the 'main' branch)
Congrats! The gnu test tests/rm/many-dir-entries-vs-OOM is now passing!
Note: The gnu test tests/env/env-signal-handler was skipped on 'main' but is now failing.

[cakebaker]

Thanks!