gcp doc only app - Batch 1

[sumoanema]

Purpose of this pull request

This pull request (PR) ...

Issue number:

Select the type of change:

• Minor Changes - Typos, formatting, slight revisions
• Update Content - Revisions and updating sections
• New Content - New features, sections, pages, tutorials
• Site and Tools - Updates, maintenance, and new packages for the site, Gatsby, React, etc

[jpipkin1]

I added Google Cloud Bigtable to the left nav with this commit: "Add Bigtable app to sidebar".

[jpipkin1]

@sumoanema, the Bigtable article is incomplete. It should follow this template: https://github.com/SumoLogic/sumologic-documentation/blob/main/docs/contributing/templates/partner-app.md

Could you take another pass at it? Take a look at other articles in the Google apps section for examples of how to write an app article:
https://help.sumologic.com/docs/integrations/google/

I'm placing this PR in draft mode until you have it ready for another review.

[sumoanema]

@kimsauce/ @jpipkin1 - the changes in this PR are for doc only apps. I have made the changes in the md file based on the feedback I got from @npande (who was working on AWS doc only apps and has merged the following docs : #2948) . Based on the same pattern I am doing it for GCP in this PR. Based on your feedback on the single md file here, I will add all the other md file to the same PR for other GCP doc only apps.

[jpipkin1]

Thanks for the clarification, @sumoanema. I apologize for not realizing that this article would be formatted like the ones in PR #2948. I'll adjust my reviews for these "doc only apps".

[JV0812]

LGTM.
index.md page will be updated once all the GCP integration docs are added, just to avoid the rework.