[7.17](backport #33006) [GCP] Update fields docs and fix inconsistencies after #27974

[mergify]

This is an automatic backport of pull request #33006 done by Mergify.
Cherry-pick of 923e11f has failed:

On branch mergify/bp/7.17/pr-33006
Your branch is up to date with 'origin/7.17'.

You are currently cherry-picking commit 923e11f24f.
  (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:   x-pack/metricbeat/module/gcp/compute/_meta/docs.asciidoc
	modified:   x-pack/metricbeat/module/gcp/gke/_meta/docs.asciidoc
	modified:   x-pack/metricbeat/module/gcp/loadbalancing/_meta/docs.asciidoc
	modified:   x-pack/metricbeat/module/gcp/pubsub/_meta/docs.asciidoc
	modified:   x-pack/metricbeat/module/gcp/storage/_meta/docs.asciidoc

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   x-pack/metricbeat/module/gcp/dataproc/_meta/docs.asciidoc
	deleted by us:   x-pack/metricbeat/module/gcp/firestore/_meta/docs.asciidoc

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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[elasticmachine]

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• Start Time: 2022-09-19T10:53:45.982+0000

• Duration: 8 min 10 sec

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[mergify]

This pull request has not been merged yet. Could you please review and merge it @endorama? 🙏