Update dependency zx to v8.7.1

[elastic-renovate-prod]

This PR contains the following updates:

Package	Type	Update	Change
zx (source)	devDependencies	minor	8.6.1 -> 8.7.1

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Release Notes

google/zx (zx)

v8.7.1: — Pipe Whisperer

Compare Source

Continues v8.7.0: handles new ps() corner case and improves $.kill mechanics on Windows #​1266 #​1267 #​1269 webpod/ps#14

v8.7.0: — Solder Savior

Compare Source

Important fixes for annoying flaky bugs

kill() 🐞

We've found an interesting case #​1262

const p = $`sleep 1000`
const {pid} = p // 12345
await p.kill()

If we kill the process again, the result might be unexpected:

await ps({pid}) // {pid: 12345, ppid: 67890, command: 'another command', ...}
p.kill()

This happens because the pid may be reused by the system for another process, so we've added extra assertions to prevent indeterminacy:

p.kill()  // Error: Too late to kill the process.
p.abort() // Error: Too late to abort the process.

ps() 🐛

• ps() uses wmic internally on Windows, it relies on fragile heuristics to parse the output. We have improved this logic to handle more format variants, but over time (in v9 maybe) we're planning to change the approach.

#​1256 #​1263 webpod/ps#12 webpod/ingrid#6

const [root] = await ps.lookup({ pid: process.pid })
assert.equal(root.pid, process.pid)

v8.6.2: — Flow Unstoppable

Compare Source

Fixes $.prefix & $.postfix values settings via env variables #​1261 #​1260

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[github-actions]

The backport to 8.x failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-8.x 8.x
# Navigate to the new working tree
cd .worktrees/backport-8.x
# Create a new branch
git switch --create backport-2928-to-8.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 c2272b1c9ab2e12e77ca8bd389020d1dbf21404a
# Push it to GitHub
git push --set-upstream origin backport-2928-to-8.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-8.x

Then, create a pull request where the base branch is 8.x and the compare/head branch is backport-2928-to-8.x.