Performance issue on calculating classes count

[Klaitos]

New Issue Checklist

• I am not disclosing a vulnerability.
• I am not just asking a question.
• I have searched through existing issues.
• I can reproduce the issue with the latest versions of Parse Server and Parse Dashboard.

Issue Description

When computing class counts, the number of documents in each collection, displayed on the sidebar, we loop on each collection and set the state for each collection. This method call the render function of the dashboard, slowing down all the process.

Steps to reproduce

With a parse-server with lots of collection (50+) : load the dashboard, try to navigate from the sidebar collection list.

Actual Outcome

Few seconds on each click to load a new page

Expected Outcome

It should be nearly instant

Environment

Localhost parse server on MacOS with nodejs 14.7

Dashboard

• Parse Dashboard version: 2.2.0
• Browser (Safari, Chrome, Firefox, Edge, etc.): Chrome
• Browser version: 93.0.4577.63

Server

• Parse Server version: 4.10.3
• Operating system: MAC OS
• Local or remote host (AWS, Azure, Google Cloud, Heroku, Digital Ocean, etc): Local

Database

• System (MongoDB or Postgres): MongoDB
• Database version: 4.4.8
• Local or remote host (MongoDB Atlas, mLab, AWS, Azure, Google Cloud, etc): Local

Logs

I'm preparing a demo and trying to open a PR for you

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[Klaitos]

Before.fix.record.mov

After my first try fix :

After.fix.1.mov

[mtrezza]

Amazing, thanks for opening this issue and submitting the PR!

[mtrezza]

Closing via #1802