Improve read operation performance of azuredevops_users data source

[rdalbuquerque]

All Submissions:

• Have you added an explanation of what your changes do and why you'd like us to include them?
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What about the current behavior has changed?

While using azuredevops_users data source to fetch all users, or even svc subject type users, the reading operation can take too long depending on the number of users on the organization.

So to improve performance, it was added a features block with concurrent_workers argument so the user can set concurrent processing for the user data source, greatly decreasing the time it takes to finish read operation.

Does this introduce a change to go.mod, go.sum or vendor/?

• Yes
• No

Does this introduce a breaking change?

• Yes
• No

Any relevant logs, error output, etc?

Without concurrent workers:

With concurrent_workers set to 10:

Other information

azuredevops_users data source with features block:

data "azuredevops_users" "users" {
  features {
    concurrent_workers = 10
  }
}

[drdamour]

pretty concerned this can make things even worse..the underlying problem with azuredevops_users is it pulls every user in cases you only want 1

[rdalbuquerque]

@drdamour on my use cases it either drastically improved performance (like the print on this PR) or stayed the same, and default is a single go routine.

Feel free to contact me with any use case that this might be negatively impacting and we can discuss possible solutions.

[xuzhang3]

@rdalbuquerque @drdamour This can be controlled by adding a custom attribute to control the number of users that can be pulled. Similar like the azuredevops_variable_group, a custom property search_depth was used to control how many secrets can be searched.