chore: Use rm instead of rmdir for recursive operations

[jbudz]

Starting in Node 16, recursive fs.rmdir calls are deprecated and will log a
warning. It's recommended to use fs.rm intead.

https://nodejs.org/api/deprecations.html#DEP0147

Kibana currently exits on process warnings, this will look like:

  ✓  Step: 'Navigates to details page' succeeded (72 ms)
(node:663222) [DEP0147] DeprecationWarning: In future versions of Node.js, fs.rmdir(path, { recursive: true }) will be removed. Use fs.rm(path, { recursive: true }) instead
(Use `node --trace-deprecation ...` to show where the warning was created)
Node.js process-warning detected:

DeprecationWarning: In future versions of Node.js, fs.rmdir(path, { recursive: true }) will be removed. Use fs.rm(path, { recursive: true }) instead
    at emitRecursiveRmdirWarning (node:internal/fs/utils:816:13)
    at Object.rmdir (node:fs:1115:5)
    at node:internal/util:363:7
    at new Promise (<anonymous>)
    at Object.rmdir [as rmdirAsync] (node:internal/util:349:12)
    at Runner.endJourney (/home/jon/dev/kibana-node-16/node_modules/@elastic/synthetics/src/core/runner.ts:356:11)
    at Runner.runJourney (/home/jon/dev/kibana-node-16/node_modules/@elastic/synthetics/src/core/runner.ts:414:18)
    at runMicrotasks (<anonymous>)
    at runNextTicks (node:internal/process/task_queues:61:5)
    at processImmediate (node:internal/timers:437:9)
    at Runner.run (/home/jon/dev/kibana-node-16/node_modules/@elastic/synthetics/src/core/runner.ts:465:11)
    at run (/home/jon/dev/kibana-node-16/node_modules/@elastic/synthetics/src/index.ts:45:12)
    at playwrightStart (/home/jon/dev/kibana-node-16/x-pack/plugins/uptime/e2e/playwright_start.ts:43:15)
    at /home/jon/dev/kibana-node-16/x-pack/plugins/uptime/e2e/playwright_start.ts:19:22
    at /home/jon/dev/kibana-node-16/node_modules/@kbn/test/target_node/functional_test_runner/functional_test_runner.js:48:17
    at FunctionalTestRunner._run (/home/jon/dev/kibana-node-16/node_modules/@kbn/test/target_node/functional_test_runner/functional_test_runner.js:105:14)

Terminating process...
node:child_process:903
    throw err;
    ^

[apmmachine]

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• Start Time: 2021-10-05T15:44:55.497+0000

• Duration: 16 min 18 sec

• Commit: 499775c

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Test	Results
Failed	0
Passed	142
Skipped	0
Total	142

🤖 GitHub comments

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[vigneshshanmugam]

Thanks for the PR @jbudz, The changes looks good

Would you be open to changing to fs/promises API instead?