[8.1](backport #30534) [libbeat | filebeat] Log error when parsing config block and disabled input on filebeat

[mergify]

This is an automatic backport of pull request #30534 done by Mergify.
Cherry-pick of b25fdf6 has failed:

On branch mergify/bp/8.1/pr-30534
Your branch is up to date with 'origin/8.1'.

You are currently cherry-picking commit b25fdf6a35.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   CHANGELOG.next.asciidoc
	modified:   filebeat/input/log/harvester.go
	modified:   filebeat/tests/system/test_stdin.py
	modified:   x-pack/libbeat/management/manager.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   filebeat/beater/crawler.go
	both modified:   libbeat/tests/system/beat/beat.py

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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• Start Time: 2022-03-03T09:08:22.968+0000

• Duration: 124 min 30 sec

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Total	46784

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